[PATCH v6 51/76] x86/sev-es: Handle instruction fetches from user-space
From: Joerg Roedel
When a #VC exception is triggered by user-space the instruction decoder
needs to read the instruction bytes from user addresses. Enhance
vc_decode_insn() to safely fetch kernel and user instructions.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-51-j...@8bytes.org
---
arch/x86/kernel/sev-es.c | 31 ++-
1 file changed, 22 insertions(+), 9 deletions(-)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 81d94f78d2d4..1493e8cf14f2 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -237,17 +237,30 @@ static enum es_result vc_decode_insn(struct es_em_ctxt
*ctxt)
enum es_result ret;
int res;
- res = vc_fetch_insn_kernel(ctxt, buffer);
- if (unlikely(res == -EFAULT)) {
- ctxt->fi.vector = X86_TRAP_PF;
- ctxt->fi.error_code = 0;
- ctxt->fi.cr2= ctxt->regs->ip;
- return ES_EXCEPTION;
+ if (user_mode(ctxt->regs)) {
+ res = insn_fetch_from_user(ctxt->regs, buffer);
+ if (!res) {
+ ctxt->fi.vector = X86_TRAP_PF;
+ ctxt->fi.error_code = X86_PF_INSTR | X86_PF_USER;
+ ctxt->fi.cr2= ctxt->regs->ip;
+ return ES_EXCEPTION;
+ }
+
+ if (!insn_decode(>insn, ctxt->regs, buffer, res))
+ return ES_DECODE_FAILED;
+ } else {
+ res = vc_fetch_insn_kernel(ctxt, buffer);
+ if (res) {
+ ctxt->fi.vector = X86_TRAP_PF;
+ ctxt->fi.error_code = X86_PF_INSTR;
+ ctxt->fi.cr2= ctxt->regs->ip;
+ return ES_EXCEPTION;
+ }
+
+ insn_init(>insn, buffer, MAX_INSN_SIZE - res, 1);
+ insn_get_length(>insn);
}
- insn_init(>insn, buffer, MAX_INSN_SIZE - res, 1);
- insn_get_length(>insn);
-
ret = ctxt->insn.immediate.got ? ES_OK : ES_DECODE_FAILED;
return ret;
--
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[PATCH v6 69/76] x86/realmode: Setup AP jump table
From: Tom Lendacky
As part of the GHCB specification, the booting of APs under SEV-ES
requires an AP jump table when transitioning from one layer of code to
another (e.g. when going from UEFI to the OS). As a result, each layer
that parks an AP must provide the physical address of an AP jump table
to the next layer via the hypervisor.
Upon booting of the kernel, read the AP jump table address from the
hypervisor. Under SEV-ES, APs are started using the INIT-SIPI-SIPI
sequence. Before issuing the first SIPI request for an AP, the start
CS and IP is programmed into the AP jump table. Upon issuing the SIPI
request, the AP will awaken and jump to that start CS:IP address.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: - Adapted to different code base
- Moved AP table setup from SIPI sending path to
real-mode setup code
- Fix sparse warnings ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-69-j...@8bytes.org
---
arch/x86/include/asm/sev-es.h | 5 +++
arch/x86/include/uapi/asm/svm.h | 3 ++
arch/x86/kernel/sev-es.c| 68 +
arch/x86/realmode/init.c| 18 -
4 files changed, 92 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h
index 2dd19932a60d..6ca38dc378e0 100644
--- a/arch/x86/include/asm/sev-es.h
+++ b/arch/x86/include/asm/sev-es.h
@@ -73,6 +73,9 @@ static inline u64 lower_bits(u64 val, unsigned int bits)
return (val & mask);
}
+struct real_mode_header;
+enum stack_type;
+
/* Early IDT entry points for #VC handler */
extern void vc_no_ghcb(void);
extern bool handle_vc_boot_ghcb(struct pt_regs *regs);
@@ -91,9 +94,11 @@ static __always_inline void sev_es_ist_exit(void)
if (static_branch_unlikely(_es_enable_key))
__sev_es_ist_exit();
}
+extern int sev_es_setup_ap_jump_table(struct real_mode_header *rmh);
#else
static inline void sev_es_ist_enter(struct pt_regs *regs) { }
static inline void sev_es_ist_exit(void) { }
+static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) {
return 0; }
#endif
#endif
diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h
index 8f36ae021a7f..a19ce9681ec2 100644
--- a/arch/x86/include/uapi/asm/svm.h
+++ b/arch/x86/include/uapi/asm/svm.h
@@ -84,6 +84,9 @@
/* SEV-ES software-defined VMGEXIT events */
#define SVM_VMGEXIT_MMIO_READ 0x8001
#define SVM_VMGEXIT_MMIO_WRITE 0x8002
+#define SVM_VMGEXIT_AP_JUMP_TABLE 0x8005
+#defineSVM_VMGEXIT_SET_AP_JUMP_TABLE 0
+#defineSVM_VMGEXIT_GET_AP_JUMP_TABLE 1
#define SVM_VMGEXIT_UNSUPPORTED_EVENT 0x8000
#define SVM_EXIT_ERR -1
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 28fe95ecd508..09a45ccd6c1d 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -21,6 +21,8 @@
#include
#include
+#include
+#include
#include
#include
#include
@@ -219,6 +221,9 @@ static __always_inline void sev_es_put_ghcb(struct
ghcb_state *state)
}
}
+/* Needed in vc_early_vc_forward_exception */
+void do_early_exception(struct pt_regs *regs, int trapnr);
+
static inline u64 sev_es_rd_ghcb_msr(void)
{
return native_read_msr(MSR_AMD64_SEV_ES_GHCB);
@@ -407,6 +412,69 @@ static bool vc_slow_virt_to_phys(struct ghcb *ghcb, struct
es_em_ctxt *ctxt,
/* Include code shared with pre-decompression boot stage */
#include "sev-es-shared.c"
+static u64 sev_es_get_jump_table_addr(void)
+{
+ struct ghcb_state state;
+ unsigned long flags;
+ struct ghcb *ghcb;
+ u64 ret;
+
+ local_irq_save(flags);
+
+ ghcb = sev_es_get_ghcb();
+
+ vc_ghcb_invalidate(ghcb);
+ ghcb_set_sw_exit_code(ghcb, SVM_VMGEXIT_AP_JUMP_TABLE);
+ ghcb_set_sw_exit_info_1(ghcb, SVM_VMGEXIT_GET_AP_JUMP_TABLE);
+ ghcb_set_sw_exit_info_2(ghcb, 0);
+
+ sev_es_wr_ghcb_msr(__pa(ghcb));
+ VMGEXIT();
+
+ if (!ghcb_sw_exit_info_1_is_valid(ghcb) ||
+ !ghcb_sw_exit_info_2_is_valid(ghcb))
+ ret = 0;
+
+ ret = ghcb->save.sw_exit_info_2;
+
+ sev_es_put_ghcb();
+
+ local_irq_restore(flags);
+
+ return ret;
+}
+
+int sev_es_setup_ap_jump_table(struct real_mode_header *rmh)
+{
+ u16 startup_cs, startup_ip;
+ phys_addr_t jump_table_pa;
+ u64 jump_table_addr;
+ u16 __iomem *jump_table;
+
+ jump_table_addr = sev_es_get_jump_table_addr();
+
+ /* Check if AP Jump Table is non-zero and page-aligned */
+ if (!jump_table_addr || jump_table_addr & ~PAGE_MASK)
+ return 0;
+
+ jump_table_pa = jump_table_addr & PAGE_MASK;
+
+ startup_cs = (u16)(rmh->trampoline_start >> 4);
+ startup_ip =
[PATCH v6 62/76] x86/sev-es: Handle VMMCALL Events
From: Tom Lendacky
Implement a handler for #VC exceptions caused by VMMCALL instructions.
This patch is only a starting point, VMMCALL emulation under SEV-ES
needs further hypervisor-specific changes to provide additional state.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: Adapt to #VC handling infrastructure ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-62-j...@8bytes.org
---
arch/x86/kernel/sev-es.c | 23 +++
1 file changed, 23 insertions(+)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 76eff9be2510..8dd8385efa6a 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -889,6 +889,26 @@ static enum es_result vc_handle_mwait(struct ghcb *ghcb,
return ES_OK;
}
+static enum es_result vc_handle_vmmcall(struct ghcb *ghcb,
+ struct es_em_ctxt *ctxt)
+{
+ enum es_result ret;
+
+ ghcb_set_rax(ghcb, ctxt->regs->ax);
+ ghcb_set_cpl(ghcb, user_mode(ctxt->regs) ? 3 : 0);
+
+ ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_VMMCALL, 0, 0);
+ if (ret != ES_OK)
+ return ret;
+
+ if (!ghcb_rax_is_valid(ghcb))
+ return ES_VMM_ERROR;
+
+ ctxt->regs->ax = ghcb->save.rax;
+
+ return ES_OK;
+}
+
static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
struct ghcb *ghcb,
unsigned long exit_code)
@@ -922,6 +942,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt
*ctxt,
case SVM_EXIT_MSR:
result = vc_handle_msr(ghcb, ctxt);
break;
+ case SVM_EXIT_VMMCALL:
+ result = vc_handle_vmmcall(ghcb, ctxt);
+ break;
case SVM_EXIT_WBINVD:
result = vc_handle_wbinvd(ghcb, ctxt);
break;
--
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[PATCH v6 60/76] x86/sev-es: Handle MONITOR/MONITORX Events
From: Tom Lendacky
Implement a handler for #VC exceptions caused by MONITOR and MONITORX
instructions.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: Adapt to #VC handling infrastructure ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-60-j...@8bytes.org
---
arch/x86/kernel/sev-es.c | 13 +
1 file changed, 13 insertions(+)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 4e1989c58df8..c7324cd0a4d6 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -872,6 +872,16 @@ static enum es_result vc_handle_rdpmc(struct ghcb *ghcb,
struct es_em_ctxt *ctxt
return ES_OK;
}
+static enum es_result vc_handle_monitor(struct ghcb *ghcb,
+ struct es_em_ctxt *ctxt)
+{
+ /*
+* Treat it as a NOP and do not leak a physical address to the
+* hypervisor
+*/
+ return ES_OK;
+}
+
static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
struct ghcb *ghcb,
unsigned long exit_code)
@@ -908,6 +918,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt
*ctxt,
case SVM_EXIT_WBINVD:
result = vc_handle_wbinvd(ghcb, ctxt);
break;
+ case SVM_EXIT_MONITOR:
+ result = vc_handle_monitor(ghcb, ctxt);
+ break;
case SVM_EXIT_NPF:
result = vc_handle_mmio(ghcb, ctxt);
break;
--
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[PATCH v6 54/76] x86/sev-es: Handle MSR events
From: Tom Lendacky
Implement a handler for #VC exceptions caused by RDMSR/WRMSR
instructions.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: Adapt to #VC handling infrastructure ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-54-j...@8bytes.org
---
arch/x86/kernel/sev-es.c | 28
1 file changed, 28 insertions(+)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 7bfd402c74e3..379f9ad63ce8 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -398,6 +398,31 @@ static bool vc_slow_virt_to_phys(struct ghcb *ghcb, struct
es_em_ctxt *ctxt,
/* Include code shared with pre-decompression boot stage */
#include "sev-es-shared.c"
+static enum es_result vc_handle_msr(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
+{
+ struct pt_regs *regs = ctxt->regs;
+ enum es_result ret;
+ u64 exit_info_1;
+
+ /* Is it a WRMSR? */
+ exit_info_1 = (ctxt->insn.opcode.bytes[1] == 0x30) ? 1 : 0;
+
+ ghcb_set_rcx(ghcb, regs->cx);
+ if (exit_info_1) {
+ ghcb_set_rax(ghcb, regs->ax);
+ ghcb_set_rdx(ghcb, regs->dx);
+ }
+
+ ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_MSR, exit_info_1, 0);
+
+ if ((ret == ES_OK) && (!exit_info_1)) {
+ regs->ax = ghcb->save.rax;
+ regs->dx = ghcb->save.rdx;
+ }
+
+ return ret;
+}
+
/*
* This function runs on the first #VC exception after the kernel
* switched to virtual addresses.
@@ -756,6 +781,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt
*ctxt,
case SVM_EXIT_IOIO:
result = vc_handle_ioio(ghcb, ctxt);
break;
+ case SVM_EXIT_MSR:
+ result = vc_handle_msr(ghcb, ctxt);
+ break;
case SVM_EXIT_NPF:
result = vc_handle_mmio(ghcb, ctxt);
break;
--
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[PATCH v6 73/76] x86/sev-es: Support CPU offline/online
From: Joerg Roedel
Add a play_dead handler when running under SEV-ES. This is needed
because the hypervisor can't deliver an SIPI request to restart the AP.
Instead the kernel has to issue a VMGEXIT to halt the VCPU until the
hypervisor wakes it up again.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-73-j...@8bytes.org
---
arch/x86/include/uapi/asm/svm.h | 1 +
arch/x86/kernel/sev-es.c| 64 +
2 files changed, 65 insertions(+)
diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h
index a19ce9681ec2..20a05839dd9a 100644
--- a/arch/x86/include/uapi/asm/svm.h
+++ b/arch/x86/include/uapi/asm/svm.h
@@ -84,6 +84,7 @@
/* SEV-ES software-defined VMGEXIT events */
#define SVM_VMGEXIT_MMIO_READ 0x8001
#define SVM_VMGEXIT_MMIO_WRITE 0x8002
+#define SVM_VMGEXIT_AP_HLT_LOOP0x8004
#define SVM_VMGEXIT_AP_JUMP_TABLE 0x8005
#defineSVM_VMGEXIT_SET_AP_JUMP_TABLE 0
#defineSVM_VMGEXIT_GET_AP_JUMP_TABLE 1
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 09a45ccd6c1d..597ebb73411f 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -29,6 +29,8 @@
#include
#include
#include
+#include
+#include
#define DR7_RESET_VALUE0x400
@@ -522,6 +524,66 @@ static bool __init sev_es_setup_ghcb(void)
return true;
}
+#ifdef CONFIG_HOTPLUG_CPU
+static void sev_es_ap_hlt_loop(void)
+{
+ struct ghcb_state state;
+ struct ghcb *ghcb;
+
+ ghcb = sev_es_get_ghcb();
+
+ while (true) {
+ vc_ghcb_invalidate(ghcb);
+ ghcb_set_sw_exit_code(ghcb, SVM_VMGEXIT_AP_HLT_LOOP);
+ ghcb_set_sw_exit_info_1(ghcb, 0);
+ ghcb_set_sw_exit_info_2(ghcb, 0);
+
+ sev_es_wr_ghcb_msr(__pa(ghcb));
+ VMGEXIT();
+
+ /* Wakeup signal? */
+ if (ghcb_sw_exit_info_2_is_valid(ghcb) &&
+ ghcb->save.sw_exit_info_2)
+ break;
+ }
+
+ sev_es_put_ghcb();
+}
+
+/*
+ * Play_dead handler when running under SEV-ES. This is needed because
+ * the hypervisor can't deliver an SIPI request to restart the AP.
+ * Instead the kernel has to issue a VMGEXIT to halt the VCPU until the
+ * hypervisor wakes it up again.
+ */
+static void sev_es_play_dead(void)
+{
+ play_dead_common();
+
+ /* IRQs now disabled */
+
+ sev_es_ap_hlt_loop();
+
+ /*
+* If we get here, the VCPU was woken up again. Jump to CPU
+* startup code to get it back online.
+*/
+
+ start_cpu();
+}
+#else /* CONFIG_HOTPLUG_CPU */
+#define sev_es_play_dead native_play_dead
+#endif /* CONFIG_HOTPLUG_CPU */
+
+#ifdef CONFIG_SMP
+static void __init sev_es_setup_play_dead(void)
+{
+ smp_ops.play_dead = sev_es_play_dead;
+}
+#else
+static inline void sev_es_setup_play_dead(void) { }
+#endif
+
static void __init sev_es_alloc_runtime_data(int cpu)
{
struct sev_es_runtime_data *data;
@@ -569,6 +631,8 @@ void __init sev_es_init_vc_handling(void)
sev_es_init_ghcb(cpu);
sev_es_setup_vc_stacks(cpu);
}
+
+ sev_es_setup_play_dead();
}
static void __init vc_early_forward_exception(struct es_em_ctxt *ctxt)
--
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[PATCH v6 71/76] x86/head/64: Don't call verify_cpu() on starting APs
From: Joerg Roedel
The APs are not ready to handle exceptions when verify_cpu() is called
in secondary_startup_64.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-71-j...@8bytes.org
---
arch/x86/include/asm/realmode.h | 1 +
arch/x86/kernel/head_64.S | 12
arch/x86/realmode/init.c| 6 ++
3 files changed, 19 insertions(+)
diff --git a/arch/x86/include/asm/realmode.h b/arch/x86/include/asm/realmode.h
index 6590394af309..5c97807c38a4 100644
--- a/arch/x86/include/asm/realmode.h
+++ b/arch/x86/include/asm/realmode.h
@@ -69,6 +69,7 @@ extern unsigned char startup_32_smp[];
extern unsigned char boot_gdt[];
#else
extern unsigned char secondary_startup_64[];
+extern unsigned char secondary_startup_64_no_verify[];
#endif
static inline size_t real_mode_size_needed(void)
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 8d5bf7c568a4..a708107688a2 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -140,6 +140,18 @@ SYM_CODE_START(secondary_startup_64)
/* Sanitize CPU configuration */
call verify_cpu
+ /*
+* The secondary_startup_64_no_verify entry point is only used by
+* SEV-ES guests. In those guests the call to verify_cpu() would cause
+* #VC exceptions which can not be handled at this stage of secondary
+* CPU bringup.
+*
+* All non SEV-ES systems, especially Intel systems, need to execute
+* verify_cpu() above to make sure NX is enabled.
+*/
+SYM_INNER_LABEL(secondary_startup_64_no_verify, SYM_L_GLOBAL)
+ UNWIND_HINT_EMPTY
+
/*
* Retrieve the modifier (SME encryption mask if SME is active) to be
* added to the initial pgdir entry that will be programmed into CR3.
diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c
index 61a52b925d15..df701f87ddef 100644
--- a/arch/x86/realmode/init.c
+++ b/arch/x86/realmode/init.c
@@ -46,6 +46,12 @@ static void sme_sev_setup_real_mode(struct trampoline_header
*th)
th->flags |= TH_FLAGS_SME_ACTIVE;
if (sev_es_active()) {
+ /*
+* Skip the call to verify_cpu() in secondary_startup_64 as it
+* will cause #VC exceptions when the AP can't handle them yet.
+*/
+ th->start = (u64) secondary_startup_64_no_verify;
+
if (sev_es_setup_ap_jump_table(real_mode_header))
panic("Failed to update SEV-ES AP Jump Table");
}
--
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[PATCH v6 58/76] x86/sev-es: Handle RDPMC Events
From: Tom Lendacky
Implement a handler for #VC exceptions caused by RDPMC instructions.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: Adapt to #VC handling infrastructure ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-58-j...@8bytes.org
---
arch/x86/kernel/sev-es.c | 22 ++
1 file changed, 22 insertions(+)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 0d8103a87ff1..e098d1e71a3e 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -853,6 +853,25 @@ static enum es_result vc_handle_wbinvd(struct ghcb *ghcb,
return sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_WBINVD, 0, 0);
}
+static enum es_result vc_handle_rdpmc(struct ghcb *ghcb, struct es_em_ctxt
*ctxt)
+{
+ enum es_result ret;
+
+ ghcb_set_rcx(ghcb, ctxt->regs->cx);
+
+ ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_RDPMC, 0, 0);
+ if (ret != ES_OK)
+ return ret;
+
+ if (!(ghcb_rax_is_valid(ghcb) && ghcb_rdx_is_valid(ghcb)))
+ return ES_VMM_ERROR;
+
+ ctxt->regs->ax = ghcb->save.rax;
+ ctxt->regs->dx = ghcb->save.rdx;
+
+ return ES_OK;
+}
+
static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
struct ghcb *ghcb,
unsigned long exit_code)
@@ -870,6 +889,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt
*ctxt,
case SVM_EXIT_RDTSCP:
result = vc_handle_rdtsc(ghcb, ctxt, exit_code);
break;
+ case SVM_EXIT_RDPMC:
+ result = vc_handle_rdpmc(ghcb, ctxt);
+ break;
case SVM_EXIT_CPUID:
result = vc_handle_cpuid(ghcb, ctxt);
break;
--
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[PATCH v6 67/76] x86/vmware: Add VMware specific handling for VMMCALL under SEV-ES
From: Doug Covelli
Add VMware specific handling for #VC faults caused by VMMCALL
instructions.
Signed-off-by: Doug Covelli
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: - Adapt to different paravirt interface ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-67-j...@8bytes.org
---
arch/x86/kernel/cpu/vmware.c | 50
1 file changed, 45 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c
index 9b6fafa69be9..924571fe5864 100644
--- a/arch/x86/kernel/cpu/vmware.c
+++ b/arch/x86/kernel/cpu/vmware.c
@@ -33,6 +33,7 @@
#include
#include
#include
+#include
#undef pr_fmt
#define pr_fmt(fmt)"vmware: " fmt
@@ -476,10 +477,49 @@ static bool __init vmware_legacy_x2apic_available(void)
(eax & (1 << VMWARE_CMD_LEGACY_X2APIC)) != 0;
}
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+static void vmware_sev_es_hcall_prepare(struct ghcb *ghcb,
+ struct pt_regs *regs)
+{
+ /* Copy VMWARE specific Hypercall parameters to the GHCB */
+ ghcb_set_rip(ghcb, regs->ip);
+ ghcb_set_rbx(ghcb, regs->bx);
+ ghcb_set_rcx(ghcb, regs->cx);
+ ghcb_set_rdx(ghcb, regs->dx);
+ ghcb_set_rsi(ghcb, regs->si);
+ ghcb_set_rdi(ghcb, regs->di);
+ ghcb_set_rbp(ghcb, regs->bp);
+}
+
+static bool vmware_sev_es_hcall_finish(struct ghcb *ghcb, struct pt_regs *regs)
+{
+ if (!(ghcb_rbx_is_valid(ghcb) &&
+ ghcb_rcx_is_valid(ghcb) &&
+ ghcb_rdx_is_valid(ghcb) &&
+ ghcb_rsi_is_valid(ghcb) &&
+ ghcb_rdi_is_valid(ghcb) &&
+ ghcb_rbp_is_valid(ghcb)))
+ return false;
+
+ regs->bx = ghcb->save.rbx;
+ regs->cx = ghcb->save.rcx;
+ regs->dx = ghcb->save.rdx;
+ regs->si = ghcb->save.rsi;
+ regs->di = ghcb->save.rdi;
+ regs->bp = ghcb->save.rbp;
+
+ return true;
+}
+#endif
+
const __initconst struct hypervisor_x86 x86_hyper_vmware = {
- .name = "VMware",
- .detect = vmware_platform,
- .type = X86_HYPER_VMWARE,
- .init.init_platform = vmware_platform_setup,
- .init.x2apic_available = vmware_legacy_x2apic_available,
+ .name = "VMware",
+ .detect = vmware_platform,
+ .type = X86_HYPER_VMWARE,
+ .init.init_platform = vmware_platform_setup,
+ .init.x2apic_available = vmware_legacy_x2apic_available,
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+ .runtime.sev_es_hcall_prepare = vmware_sev_es_hcall_prepare,
+ .runtime.sev_es_hcall_finish= vmware_sev_es_hcall_finish,
+#endif
};
--
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[PATCH v6 40/76] x86/sev-es: Print SEV-ES info into kernel log
From: Joerg Roedel
Refactor the message printed to the kernel log which indicates whether
SEV or SME is active to print a list of enabled encryption features.
This will scale better in the future when more memory encryption
features might be added. Also add SEV-ES to the list of features.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-40-j...@8bytes.org
---
arch/x86/mm/mem_encrypt.c | 29 ++---
1 file changed, 26 insertions(+), 3 deletions(-)
diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 232d6e1bcfc6..5cec395a4b0d 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c
@@ -407,6 +407,31 @@ void __init mem_encrypt_free_decrypted_mem(void)
free_init_pages("unused decrypted", vaddr, vaddr_end);
}
+static void print_mem_encrypt_feature_info(void)
+{
+ pr_info("AMD Memory Encryption Features active:");
+
+ /* Secure Memory Encryption */
+ if (sme_active()) {
+ /*
+* SME is mutually exclusive with any of the SEV
+* features below.
+*/
+ pr_cont(" SME\n");
+ return;
+ }
+
+ /* Secure Encrypted Virtualization */
+ if (sev_active())
+ pr_cont(" SEV");
+
+ /* Encrypted Register State */
+ if (sev_es_active())
+ pr_cont(" SEV-ES");
+
+ pr_cont("\n");
+}
+
/* Architecture __weak replacement functions */
void __init mem_encrypt_init(void)
{
@@ -422,8 +447,6 @@ void __init mem_encrypt_init(void)
if (sev_active())
static_branch_enable(_enable_key);
- pr_info("AMD %s active\n",
- sev_active() ? "Secure Encrypted Virtualization (SEV)"
-: "Secure Memory Encryption (SME)");
+ print_mem_encrypt_feature_info();
}
--
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[PATCH v6 44/76] x86/sev-es: Setup per-cpu GHCBs for the runtime handler
From: Tom Lendacky
The runtime handler needs a GHCB per CPU. Set them up and map them
unencrypted.
Signed-off-by: Tom Lendacky
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-44-j...@8bytes.org
---
arch/x86/include/asm/mem_encrypt.h | 2 ++
arch/x86/kernel/sev-es.c | 56 +-
arch/x86/kernel/traps.c| 3 ++
3 files changed, 60 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/mem_encrypt.h
b/arch/x86/include/asm/mem_encrypt.h
index 4e72b73a9cb5..c9f5df0a1c10 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h
@@ -49,6 +49,7 @@ void __init mem_encrypt_free_decrypted_mem(void);
/* Architecture __weak replacement functions */
void __init mem_encrypt_init(void);
+void __init sev_es_init_vc_handling(void);
bool sme_active(void);
bool sev_active(void);
bool sev_es_active(void);
@@ -72,6 +73,7 @@ static inline void __init sme_early_init(void) { }
static inline void __init sme_encrypt_kernel(struct boot_params *bp) { }
static inline void __init sme_enable(struct boot_params *bp) { }
+static inline void sev_es_init_vc_handling(void) { }
static inline bool sme_active(void) { return false; }
static inline bool sev_active(void) { return false; }
static inline bool sev_es_active(void) { return false; }
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index bb3e702a71eb..734afaee378d 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -8,8 +8,13 @@
*/
#include /* For show_regs() */
-#include
+#include
+#include
#include
+#include
+#include
+#include
+#include
#include
#include
@@ -29,6 +34,13 @@ static struct ghcb boot_ghcb_page __bss_decrypted
__aligned(PAGE_SIZE);
*/
static struct ghcb __initdata *boot_ghcb;
+/* #VC handler runtime per-cpu data */
+struct sev_es_runtime_data {
+ struct ghcb ghcb_page;
+};
+
+static DEFINE_PER_CPU(struct sev_es_runtime_data*, runtime_data);
+
/* Needed in vc_early_forward_exception */
void do_early_exception(struct pt_regs *regs, int trapnr);
@@ -198,6 +210,48 @@ static bool __init sev_es_setup_ghcb(void)
return true;
}
+static void __init sev_es_alloc_runtime_data(int cpu)
+{
+ struct sev_es_runtime_data *data;
+
+ data = memblock_alloc(sizeof(*data), PAGE_SIZE);
+ if (!data)
+ panic("Can't allocate SEV-ES runtime data");
+
+ per_cpu(runtime_data, cpu) = data;
+}
+
+static void __init sev_es_init_ghcb(int cpu)
+{
+ struct sev_es_runtime_data *data;
+ int err;
+
+ data = per_cpu(runtime_data, cpu);
+
+ err = early_set_memory_decrypted((unsigned long)>ghcb_page,
+sizeof(data->ghcb_page));
+ if (err)
+ panic("Can not map GHCBs unencrypted");
+
+ memset(>ghcb_page, 0, sizeof(data->ghcb_page));
+}
+
+void __init sev_es_init_vc_handling(void)
+{
+ int cpu;
+
+ BUILD_BUG_ON((offsetof(struct sev_es_runtime_data, ghcb_page) %
PAGE_SIZE) != 0);
+
+ if (!sev_es_active())
+ return;
+
+ /* Initialize per-cpu GHCB pages */
+ for_each_possible_cpu(cpu) {
+ sev_es_alloc_runtime_data(cpu);
+ sev_es_init_ghcb(cpu);
+ }
+}
+
static void __init vc_early_forward_exception(struct es_em_ctxt *ctxt)
{
int trapnr = ctxt->fi.vector;
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 1f66d2d1e998..74cfe6eb7ebb 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -1077,6 +1077,9 @@ void __init trap_init(void)
/* Init cpu_entry_area before IST entries are set up */
setup_cpu_entry_areas();
+ /* Init GHCB memory pages when running as an SEV-ES guest */
+ sev_es_init_vc_handling();
+
idt_setup_traps();
/*
--
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[PATCH v6 43/76] x86/sev-es: Setup GHCB based boot #VC handler
From: Joerg Roedel
Add the infrastructure to handle #VC exceptions when the kernel runs
on virtual addresses and has a GHCB mapped. This handler will be used
until the runtime #VC handler takes over.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-43-j...@8bytes.org
---
arch/x86/include/asm/segment.h | 2 +-
arch/x86/include/asm/sev-es.h | 1 +
arch/x86/kernel/head64.c| 6 ++
arch/x86/kernel/sev-es-shared.c | 14 ++--
arch/x86/kernel/sev-es.c| 116
arch/x86/mm/extable.c | 1 +
6 files changed, 132 insertions(+), 8 deletions(-)
diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h
index 517920928989..7fdd4facfce7 100644
--- a/arch/x86/include/asm/segment.h
+++ b/arch/x86/include/asm/segment.h
@@ -226,7 +226,7 @@
#define NUM_EXCEPTION_VECTORS 32
/* Bitmask of exception vectors which push an error code on the stack: */
-#define EXCEPTION_ERRCODE_MASK 0x00027d00
+#define EXCEPTION_ERRCODE_MASK 0x20027d00
#define GDT_SIZE (GDT_ENTRIES*8)
#define GDT_ENTRY_TLS_ENTRIES 3
diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h
index ec0e112a742b..824e9e6b067c 100644
--- a/arch/x86/include/asm/sev-es.h
+++ b/arch/x86/include/asm/sev-es.h
@@ -75,5 +75,6 @@ static inline u64 lower_bits(u64 val, unsigned int bits)
/* Early IDT entry points for #VC handler */
extern void vc_no_ghcb(void);
+extern bool handle_vc_boot_ghcb(struct pt_regs *regs);
#endif
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 250fae33bf66..ce2d8284edb9 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -403,6 +403,12 @@ void __init do_early_exception(struct pt_regs *regs, int
trapnr)
early_make_pgtable(native_read_cr2()))
return;
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+ if (trapnr == X86_TRAP_VC &&
+ handle_vc_boot_ghcb(regs))
+ return;
+#endif
+
early_fixup_exception(regs, trapnr);
}
diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c
index 18619279a46f..aa77f2eb8d88 100644
--- a/arch/x86/kernel/sev-es-shared.c
+++ b/arch/x86/kernel/sev-es-shared.c
@@ -9,7 +9,7 @@
* and is included directly into both code-bases.
*/
-static void __maybe_unused sev_es_terminate(unsigned int reason)
+static void sev_es_terminate(unsigned int reason)
{
u64 val = GHCB_SEV_TERMINATE;
@@ -27,7 +27,7 @@ static void __maybe_unused sev_es_terminate(unsigned int
reason)
asm volatile("hlt\n" : : : "memory");
}
-static bool __maybe_unused sev_es_negotiate_protocol(void)
+static bool sev_es_negotiate_protocol(void)
{
u64 val;
@@ -46,7 +46,7 @@ static bool __maybe_unused sev_es_negotiate_protocol(void)
return true;
}
-static void __maybe_unused vc_ghcb_invalidate(struct ghcb *ghcb)
+static void vc_ghcb_invalidate(struct ghcb *ghcb)
{
memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap));
}
@@ -58,9 +58,9 @@ static bool vc_decoding_needed(unsigned long exit_code)
exit_code <= SVM_EXIT_LAST_EXCP);
}
-static enum es_result __maybe_unused vc_init_em_ctxt(struct es_em_ctxt *ctxt,
-struct pt_regs *regs,
-unsigned long exit_code)
+static enum es_result vc_init_em_ctxt(struct es_em_ctxt *ctxt,
+ struct pt_regs *regs,
+ unsigned long exit_code)
{
enum es_result ret = ES_OK;
@@ -73,7 +73,7 @@ static enum es_result __maybe_unused vc_init_em_ctxt(struct
es_em_ctxt *ctxt,
return ret;
}
-static void __maybe_unused vc_finish_insn(struct es_em_ctxt *ctxt)
+static void vc_finish_insn(struct es_em_ctxt *ctxt)
{
ctxt->regs->ip += ctxt->insn.length;
}
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 0b698b653c0b..bb3e702a71eb 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -7,7 +7,9 @@
* Author: Joerg Roedel
*/
+#include /* For show_regs() */
#include
+#include
#include
#include
@@ -18,6 +20,18 @@
#include
#include
+/* For early boot hypervisor communication in SEV-ES enabled guests */
+static struct ghcb boot_ghcb_page __bss_decrypted __aligned(PAGE_SIZE);
+
+/*
+ * Needs to be in the .data section because we need it NULL before bss is
+ * cleared
+ */
+static struct ghcb __initdata *boot_ghcb;
+
+/* Needed in vc_early_forward_exception */
+void do_early_exception(struct pt_regs *regs, int trapnr);
+
static inline u64 sev_es_rd_ghcb_msr(void)
{
return native_read_msr(MSR_AMD64_SEV_ES_GHCB);
@@ -161,3 +175,105 @@ static enum es_result vc_read_mem(struct es_em_ctxt *ctxt,
/* Include code shared with pre-decompression boot stage */
#include "sev-es-shared.c"
+
[PATCH v6 52/76] x86/sev-es: Handle MMIO events
From: Tom Lendacky
Add handler for VC exceptions caused by MMIO intercepts. These
intercepts come along as nested page faults on pages with reserved
bits set.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: Adapt to VC handling framework ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-52-j...@8bytes.org
---
arch/x86/include/uapi/asm/svm.h | 5 +
arch/x86/kernel/sev-es.c| 220
2 files changed, 225 insertions(+)
diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h
index c68d1618c9b0..8f36ae021a7f 100644
--- a/arch/x86/include/uapi/asm/svm.h
+++ b/arch/x86/include/uapi/asm/svm.h
@@ -81,6 +81,11 @@
#define SVM_EXIT_AVIC_INCOMPLETE_IPI 0x401
#define SVM_EXIT_AVIC_UNACCELERATED_ACCESS 0x402
+/* SEV-ES software-defined VMGEXIT events */
+#define SVM_VMGEXIT_MMIO_READ 0x8001
+#define SVM_VMGEXIT_MMIO_WRITE 0x8002
+#define SVM_VMGEXIT_UNSUPPORTED_EVENT 0x8000
+
#define SVM_EXIT_ERR -1
#define SVM_EXIT_REASONS \
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 1493e8cf14f2..fa1fa55fd8e3 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -364,6 +364,37 @@ static enum es_result vc_read_mem(struct es_em_ctxt *ctxt,
return ES_EXCEPTION;
}
+static bool vc_slow_virt_to_phys(struct ghcb *ghcb, struct es_em_ctxt *ctxt,
+unsigned long vaddr, phys_addr_t *paddr)
+{
+ unsigned long va = (unsigned long)vaddr;
+ unsigned int level;
+ phys_addr_t pa;
+ pgd_t *pgd;
+ pte_t *pte;
+
+ pgd = __va(read_cr3_pa());
+ pgd = [pgd_index(va)];
+ pte = lookup_address_in_pgd(pgd, va, );
+ if (!pte) {
+ ctxt->fi.vector = X86_TRAP_PF;
+ ctxt->fi.cr2= vaddr;
+ ctxt->fi.error_code = 0;
+
+ if (user_mode(ctxt->regs))
+ ctxt->fi.error_code |= X86_PF_USER;
+
+ return false;
+ }
+
+ pa = (phys_addr_t)pte_pfn(*pte) << PAGE_SHIFT;
+ pa |= va & ~page_level_mask(level);
+
+ *paddr = pa;
+
+ return true;
+}
+
/* Include code shared with pre-decompression boot stage */
#include "sev-es-shared.c"
@@ -449,6 +480,192 @@ static void __init vc_early_forward_exception(struct
es_em_ctxt *ctxt)
do_early_exception(ctxt->regs, trapnr);
}
+static long *vc_insn_get_reg(struct es_em_ctxt *ctxt)
+{
+ long *reg_array;
+ int offset;
+
+ reg_array = (long *)ctxt->regs;
+ offset= insn_get_modrm_reg_off(>insn, ctxt->regs);
+
+ if (offset < 0)
+ return NULL;
+
+ offset /= sizeof(long);
+
+ return reg_array + offset;
+}
+
+static enum es_result vc_do_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt,
+unsigned int bytes, bool read)
+{
+ u64 exit_code, exit_info_1, exit_info_2;
+ unsigned long ghcb_pa = __pa(ghcb);
+ phys_addr_t paddr;
+ void __user *ref;
+
+ ref = insn_get_addr_ref(>insn, ctxt->regs);
+ if (ref == (void __user *)-1L)
+ return ES_UNSUPPORTED;
+
+ exit_code = read ? SVM_VMGEXIT_MMIO_READ : SVM_VMGEXIT_MMIO_WRITE;
+
+ if (!vc_slow_virt_to_phys(ghcb, ctxt, (unsigned long)ref, )) {
+ if (!read)
+ ctxt->fi.error_code |= X86_PF_WRITE;
+
+ return ES_EXCEPTION;
+ }
+
+ exit_info_1 = paddr;
+ exit_info_2 = bytes;/* Can never be greater than 8 */
+
+ ghcb->save.sw_scratch = ghcb_pa + offsetof(struct ghcb, shared_buffer);
+
+ return sev_es_ghcb_hv_call(ghcb, ctxt, exit_code, exit_info_1,
exit_info_2);
+}
+
+static enum es_result vc_handle_mmio_twobyte_ops(struct ghcb *ghcb,
+struct es_em_ctxt *ctxt)
+{
+ struct insn *insn = >insn;
+ unsigned int bytes = 0;
+ enum es_result ret;
+ int sign_byte;
+ long *reg_data;
+
+ switch (insn->opcode.bytes[1]) {
+ /* MMIO Read w/ zero-extension */
+ case 0xb6:
+ bytes = 1;
+ fallthrough;
+ case 0xb7:
+ if (!bytes)
+ bytes = 2;
+
+ ret = vc_do_mmio(ghcb, ctxt, bytes, true);
+ if (ret)
+ break;
+
+ /* Zero extend based on operand size */
+ reg_data = vc_insn_get_reg(ctxt);
+ if (!reg_data)
+ return ES_DECODE_FAILED;
+
+ memset(reg_data, 0, insn->opnd_bytes);
+
+ memcpy(reg_data, ghcb->shared_buffer, bytes);
+ break;
+
+ /* MMIO Read w/ sign-extension */
+ case 0xbe:
+ bytes = 1;
+ fallthrough;
+ case 0xbf:
+
[PATCH v6 63/76] x86/sev-es: Handle #AC Events
From: Joerg Roedel
Implement a handler for #VC exceptions caused by #AC exceptions. The #AC
exception is just forwarded to do_alignment_check() and not pushed down
to the hypervisor, as requested by the SEV-ES GHCB Standardization
Specification.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-63-j...@8bytes.org
---
arch/x86/kernel/sev-es.c | 19 +++
1 file changed, 19 insertions(+)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 8dd8385efa6a..ee0950f01590 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -909,6 +909,19 @@ static enum es_result vc_handle_vmmcall(struct ghcb *ghcb,
return ES_OK;
}
+static enum es_result vc_handle_trap_ac(struct ghcb *ghcb,
+ struct es_em_ctxt *ctxt)
+{
+ /*
+* Calling ecx_alignment_check() directly does not work, because it
+* enables IRQs and the GHCB is active. Forward the exception and call
+* it later from vc_forward_exception().
+*/
+ ctxt->fi.vector = X86_TRAP_AC;
+ ctxt->fi.error_code = 0;
+ return ES_EXCEPTION;
+}
+
static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
struct ghcb *ghcb,
unsigned long exit_code)
@@ -922,6 +935,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt
*ctxt,
case SVM_EXIT_WRITE_DR7:
result = vc_handle_dr7_write(ghcb, ctxt);
break;
+ case SVM_EXIT_EXCP_BASE + X86_TRAP_AC:
+ result = vc_handle_trap_ac(ghcb, ctxt);
+ break;
case SVM_EXIT_RDTSC:
case SVM_EXIT_RDTSCP:
result = vc_handle_rdtsc(ghcb, ctxt, exit_code);
@@ -981,6 +997,9 @@ static __always_inline void vc_forward_exception(struct
es_em_ctxt *ctxt)
case X86_TRAP_UD:
exc_invalid_op(ctxt->regs);
break;
+ case X86_TRAP_AC:
+ exc_alignment_check(ctxt->regs, error_code);
+ break;
default:
pr_emerg("Unsupported exception in #VC instruction emulation -
can't continue\n");
BUG();
--
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[PATCH v6 45/76] x86/sev-es: Allocate and Map IST stack for #VC handler
From: Joerg Roedel
Allocate and map an IST stack and an additional fall-back stack for
the #VC handler. The memory for the stacks is allocated only when
SEV-ES is active.
The #VC handler needs to use an IST stack because it could be raised
from kernel space with unsafe stack, e.g. in the SYSCALL entry path.
Since the #VC exception can be nested, the #VC handler switches back to
the interrupted stack when entered from kernel space. If switching back
is not possible the fall-back stack is used.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-45-j...@8bytes.org
---
arch/x86/include/asm/cpu_entry_area.h | 33 +--
arch/x86/include/asm/page_64_types.h | 1 +
arch/x86/kernel/cpu/common.c | 2 ++
arch/x86/kernel/dumpstack_64.c| 8 +--
arch/x86/kernel/sev-es.c | 33 +++
5 files changed, 63 insertions(+), 14 deletions(-)
diff --git a/arch/x86/include/asm/cpu_entry_area.h
b/arch/x86/include/asm/cpu_entry_area.h
index 8902fdb7de13..f87e4c0c16f4 100644
--- a/arch/x86/include/asm/cpu_entry_area.h
+++ b/arch/x86/include/asm/cpu_entry_area.h
@@ -11,25 +11,29 @@
#ifdef CONFIG_X86_64
/* Macro to enforce the same ordering and stack sizes */
-#define ESTACKS_MEMBERS(guardsize) \
- charDF_stack_guard[guardsize]; \
- charDF_stack[EXCEPTION_STKSZ]; \
- charNMI_stack_guard[guardsize]; \
- charNMI_stack[EXCEPTION_STKSZ]; \
- charDB_stack_guard[guardsize]; \
- charDB_stack[EXCEPTION_STKSZ]; \
- charMCE_stack_guard[guardsize]; \
- charMCE_stack[EXCEPTION_STKSZ]; \
- charIST_top_guard[guardsize]; \
+#define ESTACKS_MEMBERS(guardsize, optional_stack_size)\
+ charDF_stack_guard[guardsize]; \
+ charDF_stack[EXCEPTION_STKSZ]; \
+ charNMI_stack_guard[guardsize]; \
+ charNMI_stack[EXCEPTION_STKSZ]; \
+ charDB_stack_guard[guardsize]; \
+ charDB_stack[EXCEPTION_STKSZ]; \
+ charMCE_stack_guard[guardsize]; \
+ charMCE_stack[EXCEPTION_STKSZ]; \
+ charVC_stack_guard[guardsize]; \
+ charVC_stack[optional_stack_size]; \
+ charVC2_stack_guard[guardsize]; \
+ charVC2_stack[optional_stack_size]; \
+ charIST_top_guard[guardsize]; \
/* The exception stacks' physical storage. No guard pages required */
struct exception_stacks {
- ESTACKS_MEMBERS(0)
+ ESTACKS_MEMBERS(0, 0)
};
/* The effective cpu entry area mapping with guard pages. */
struct cea_exception_stacks {
- ESTACKS_MEMBERS(PAGE_SIZE)
+ ESTACKS_MEMBERS(PAGE_SIZE, EXCEPTION_STKSZ)
};
/*
@@ -40,6 +44,8 @@ enum exception_stack_ordering {
ESTACK_NMI,
ESTACK_DB,
ESTACK_MCE,
+ ESTACK_VC,
+ ESTACK_VC2,
N_EXCEPTION_STACKS
};
@@ -139,4 +145,7 @@ static inline struct entry_stack *cpu_entry_stack(int cpu)
#define __this_cpu_ist_top_va(name)\
CEA_ESTACK_TOP(__this_cpu_read(cea_exception_stacks), name)
+#define __this_cpu_ist_bot_va(name)\
+ CEA_ESTACK_BOT(__this_cpu_read(cea_exception_stacks), name)
+
#endif
diff --git a/arch/x86/include/asm/page_64_types.h
b/arch/x86/include/asm/page_64_types.h
index 288b065955b7..d0c6c10c18a0 100644
--- a/arch/x86/include/asm/page_64_types.h
+++ b/arch/x86/include/asm/page_64_types.h
@@ -28,6 +28,7 @@
#defineIST_INDEX_NMI 1
#defineIST_INDEX_DB2
#defineIST_INDEX_MCE 3
+#defineIST_INDEX_VC4
/*
* Set __PAGE_OFFSET to the most negative possible address +
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 8aa20bc2f1ca..1d65365363a1 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1821,6 +1821,8 @@ static inline void tss_setup_ist(struct tss_struct *tss)
tss->x86_tss.ist[IST_INDEX_NMI] = __this_cpu_ist_top_va(NMI);
tss->x86_tss.ist[IST_INDEX_DB] = __this_cpu_ist_top_va(DB);
tss->x86_tss.ist[IST_INDEX_MCE] = __this_cpu_ist_top_va(MCE);
+ /* Only mapped when SEV-ES is active */
+ tss->x86_tss.ist[IST_INDEX_VC] = __this_cpu_ist_top_va(VC);
}
#else /* CONFIG_X86_64 */
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index 4a94d38cd141..c49cf594714b 100644
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -24,11 +24,13 @@ static const char * const exception_stack_names[] = {
[ ESTACK_NMI
[PATCH v6 64/76] x86/sev-es: Handle #DB Events
From: Joerg Roedel
Handle #VC exceptions caused by #DB exceptions in the guest. Those
must be handled outside of instrumentation_begin()/end() so that the
handler will not be raised recursivly.
Handle them by calling the kernels debug exception handler.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-64-j...@8bytes.org
---
arch/x86/kernel/sev-es.c | 17 +
1 file changed, 17 insertions(+)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index ee0950f01590..e1f3ebbcc122 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -922,6 +922,14 @@ static enum es_result vc_handle_trap_ac(struct ghcb *ghcb,
return ES_EXCEPTION;
}
+static __always_inline void vc_handle_trap_db(struct pt_regs *regs)
+{
+ if (user_mode(regs))
+ noist_exc_debug(regs);
+ else
+ exc_debug(regs);
+}
+
static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
struct ghcb *ghcb,
unsigned long exit_code)
@@ -1033,6 +1041,15 @@ DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication)
struct ghcb *ghcb;
lockdep_assert_irqs_disabled();
+
+ /*
+* Handle #DB before calling into !noinstr code to avoid recursive #DB.
+*/
+ if (error_code == SVM_EXIT_EXCP_BASE + X86_TRAP_DB) {
+ vc_handle_trap_db(regs);
+ return;
+ }
+
instrumentation_begin();
/*
--
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[PATCH v6 49/76] x86/sev-es: Add Runtime #VC Exception Handler
From: Tom Lendacky
Add the handlers for #VC exceptions invoked at runtime.
Signed-off-by: Tom Lendacky
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-49-j...@8bytes.org
---
arch/x86/include/asm/idtentry.h | 6 +
arch/x86/kernel/idt.c | 11 +-
arch/x86/kernel/sev-es.c| 242 +++-
3 files changed, 251 insertions(+), 8 deletions(-)
diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h
index 5ce67113a761..3d2572760ce4 100644
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -318,6 +318,7 @@ static __always_inline void __##func(struct pt_regs *regs)
*/
#define DECLARE_IDTENTRY_VC(vector, func) \
DECLARE_IDTENTRY_RAW_ERRORCODE(vector, func); \
+ __visible noinstr void ist_##func(struct pt_regs *regs, unsigned long
error_code); \
__visible noinstr void safe_stack_##func(struct pt_regs *regs, unsigned
long error_code)
/**
@@ -608,6 +609,11 @@ DECLARE_IDTENTRY_RAW(X86_TRAP_DB, xenpv_exc_debug);
/* #DF */
DECLARE_IDTENTRY_DF(X86_TRAP_DF, exc_double_fault);
+/* #VC */
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+DECLARE_IDTENTRY_VC(X86_TRAP_VC, exc_vmm_communication);
+#endif
+
#ifdef CONFIG_XEN_PV
DECLARE_IDTENTRY_XENCB(X86_TRAP_OTHER, exc_xen_hypervisor_callback);
#endif
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index 0d560a1218e1..3e68741cd4de 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -265,11 +265,14 @@ static const __initconst struct idt_data early_pf_idts[]
= {
* cpu_init() when the TSS has been initialized.
*/
static const __initconst struct idt_data ist_idts[] = {
- ISTG(X86_TRAP_DB, asm_exc_debug, IST_INDEX_DB),
- ISTG(X86_TRAP_NMI, asm_exc_nmi,IST_INDEX_NMI),
- ISTG(X86_TRAP_DF, asm_exc_double_fault, IST_INDEX_DF),
+ ISTG(X86_TRAP_DB, asm_exc_debug, IST_INDEX_DB),
+ ISTG(X86_TRAP_NMI, asm_exc_nmi,IST_INDEX_NMI),
+ ISTG(X86_TRAP_DF, asm_exc_double_fault, IST_INDEX_DF),
#ifdef CONFIG_X86_MCE
- ISTG(X86_TRAP_MC, asm_exc_machine_check, IST_INDEX_MCE),
+ ISTG(X86_TRAP_MC, asm_exc_machine_check, IST_INDEX_MCE),
+#endif
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+ ISTG(X86_TRAP_VC, asm_exc_vmm_communication, IST_INDEX_VC),
#endif
};
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 95831d103418..be4b00d18923 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -7,9 +7,12 @@
* Author: Joerg Roedel
*/
+#define pr_fmt(fmt)"SEV-ES: " fmt
+
#include /* For show_regs() */
#include
#include
+#include
#include
#include
#include
@@ -22,8 +25,7 @@
#include
#include
#include
-#include
-#include
+#include
#include
/* For early boot hypervisor communication in SEV-ES enabled guests */
@@ -48,6 +50,35 @@ struct sev_es_runtime_data {
* interrupted stack in the #VC entry code.
*/
char fallback_stack[EXCEPTION_STKSZ] __aligned(PAGE_SIZE);
+
+ /*
+* Reserve one page per CPU as backup storage for the unencrypted GHCB.
+* It is needed when an NMI happens while the #VC handler uses the real
+* GHCB, and the NMI handler itself is causing another #VC exception. In
+* that case the GHCB content of the first handler needs to be backed up
+* and restored.
+*/
+ struct ghcb backup_ghcb;
+
+ /*
+* Mark the per-cpu GHCBs as in-use to detect nested #VC exceptions.
+* There is no need for it to be atomic, because nothing is written to
+* the GHCB between the read and the write of ghcb_active. So it is safe
+* to use it when a nested #VC exception happens before the write.
+*
+* This is necessary for example in the #VC->NMI->#VC case when the NMI
+* happens while the first #VC handler uses the GHCB. When the NMI code
+* raises a second #VC handler it might overwrite the contents of the
+* GHCB written by the first handler. To avoid this the content of the
+* GHCB is saved and restored when the GHCB is detected to be in use
+* already.
+*/
+ bool ghcb_active;
+ bool backup_ghcb_active;
+};
+
+struct ghcb_state {
+ struct ghcb *ghcb;
};
static DEFINE_PER_CPU(struct sev_es_runtime_data*, runtime_data);
@@ -55,6 +86,9 @@ static DEFINE_PER_CPU(struct sev_es_runtime_data*,
runtime_data);
DEFINE_STATIC_KEY_FALSE(sev_es_enable_key);
EXPORT_SYMBOL_GPL(sev_es_enable_key);
+/* Needed in vc_early_forward_exception */
+void do_early_exception(struct pt_regs *regs, int trapnr);
+
static void __init sev_es_setup_vc_stacks(int cpu)
{
struct sev_es_runtime_data *data;
@@ -129,8 +163,52 @@ void noinstr
[PATCH v6 42/76] x86/sev-es: Setup early #VC handler
From: Joerg Roedel
Setup an early handler for #VC exceptions. There is no GHCB mapped
yet, so just re-use the vc_no_ghcb_handler. It can only handle CPUID
exit-codes, but that should be enough to get the kernel through
verify_cpu() and __startup_64() until it runs on virtual addresses.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-42-j...@8bytes.org
---
arch/x86/include/asm/setup.h | 1 +
arch/x86/include/asm/sev-es.h | 3 +++
arch/x86/kernel/head64.c | 1 +
arch/x86/kernel/head_64.S | 34 +
arch/x86/kernel/idt.c | 36 +++
5 files changed, 75 insertions(+)
diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h
index cafae86813ae..0ce6453c9272 100644
--- a/arch/x86/include/asm/setup.h
+++ b/arch/x86/include/asm/setup.h
@@ -53,6 +53,7 @@ extern unsigned long __startup_secondary_64(void);
extern void startup_64_setup_env(unsigned long physbase);
extern void early_idt_setup_early_handler(unsigned long physaddr);
extern void early_load_idt(void);
+extern void early_idt_setup(unsigned long physbase);
extern void __init do_early_exception(struct pt_regs *regs, int trapnr);
#ifdef CONFIG_X86_INTEL_MID
diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h
index 7c0807b84546..ec0e112a742b 100644
--- a/arch/x86/include/asm/sev-es.h
+++ b/arch/x86/include/asm/sev-es.h
@@ -73,4 +73,7 @@ static inline u64 lower_bits(u64 val, unsigned int bits)
return (val & mask);
}
+/* Early IDT entry points for #VC handler */
+extern void vc_no_ghcb(void);
+
#endif
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 41514ec1e6f0..250fae33bf66 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -39,6 +39,7 @@
#include
#include
#include
+#include
/*
* Manage page tables very early on.
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 4622940134a5..12bf6f11fd83 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -95,6 +95,13 @@ SYM_CODE_START_NOALIGN(startup_64)
.Lon_kernel_cs:
UNWIND_HINT_EMPTY
+ /* Setup IDT - Needed for SEV-ES */
+ pushq %rsi
+ /* early_idt_setup - physbase as first parameter */
+ leaq_text(%rip), %rdi
+ callearly_idt_setup
+ popq%rsi
+
/* Sanitize CPU configuration */
call verify_cpu
@@ -363,6 +370,33 @@ SYM_CODE_START_LOCAL(early_idt_handler_common)
jmp restore_regs_and_return_to_kernel
SYM_CODE_END(early_idt_handler_common)
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+/*
+ * VC Exception handler used during very early boot. The
+ * early_idt_handler_array can't be used because it returns via the
+ * paravirtualized INTERRUPT_RETURN and pv-ops don't work that early.
+ */
+SYM_CODE_START_NOALIGN(vc_no_ghcb)
+ UNWIND_HINT_IRET_REGS offset=8
+
+ /* Build pt_regs */
+ PUSH_AND_CLEAR_REGS
+
+ /* Call C handler */
+ movq%rsp, %rdi
+ movqORIG_RAX(%rsp), %rsi
+ calldo_vc_no_ghcb
+
+ /* Unwind pt_regs */
+ POP_REGS
+
+ /* Remove Error Code */
+ addq$8, %rsp
+
+ /* Pure iret required here - don't use INTERRUPT_RETURN */
+ iretq
+SYM_CODE_END(vc_no_ghcb)
+#endif
#define SYM_DATA_START_PAGE_ALIGNED(name) \
SYM_START(name, SYM_L_GLOBAL, .balign PAGE_SIZE)
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index e2777cc264f5..0d560a1218e1 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -11,6 +11,7 @@
#include
#include
#include
+#include
struct idt_data {
unsigned intvector;
@@ -408,3 +409,38 @@ void early_load_idt(void)
{
load_idt(_descr);
}
+
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+static void set_early_idt_handler(gate_desc *idt, int n, void *handler)
+{
+ struct idt_data data;
+ gate_desc desc;
+
+ init_idt_data(, n, handler);
+ idt_init_desc(, );
+ native_write_idt_entry(idt, n, );
+}
+#endif
+
+static struct desc_ptr early_idt_descr __initdata = {
+ .size = IDT_TABLE_SIZE - 1,
+ .address= 0 /* Needs physical address of idt_table -
initialized at runtime. */,
+};
+
+void __init early_idt_setup(unsigned long physbase)
+{
+ void __maybe_unused *handler;
+ gate_desc *idt;
+
+ idt = fixup_pointer(idt_table, physbase);
+
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+ /* VMM Communication Exception */
+ handler = fixup_pointer(vc_no_ghcb, physbase);
+ set_early_idt_handler(idt, X86_TRAP_VC, handler);
+#endif
+
+ /* Initialize IDT descriptor and load IDT */
+ early_idt_descr.address = (unsigned long)idt;
+ native_load_idt(_idt_descr);
+}
--
2.28.0
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[PATCH v6 50/76] x86/sev-es: Wire up existing #VC exit-code handlers
From: Joerg Roedel
Re-use the handlers for CPUID and IOIO caused #VC exceptions in the
early boot handler.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-50-j...@8bytes.org
---
arch/x86/kernel/sev-es-shared.c | 7 +++
arch/x86/kernel/sev-es.c| 6 ++
2 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c
index aa77f2eb8d88..a6b41910b8ab 100644
--- a/arch/x86/kernel/sev-es-shared.c
+++ b/arch/x86/kernel/sev-es-shared.c
@@ -325,8 +325,7 @@ static enum es_result vc_ioio_exitinfo(struct es_em_ctxt
*ctxt, u64 *exitinfo)
return ES_OK;
}
-static enum es_result __maybe_unused
-vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
+static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt
*ctxt)
{
struct pt_regs *regs = ctxt->regs;
u64 exit_info_1, exit_info_2;
@@ -434,8 +433,8 @@ vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
return ret;
}
-static enum es_result __maybe_unused vc_handle_cpuid(struct ghcb *ghcb,
-struct es_em_ctxt *ctxt)
+static enum es_result vc_handle_cpuid(struct ghcb *ghcb,
+ struct es_em_ctxt *ctxt)
{
struct pt_regs *regs = ctxt->regs;
u32 cr4 = native_read_cr4();
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index be4b00d18923..81d94f78d2d4 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -443,6 +443,12 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt
*ctxt,
enum es_result result;
switch (exit_code) {
+ case SVM_EXIT_CPUID:
+ result = vc_handle_cpuid(ghcb, ctxt);
+ break;
+ case SVM_EXIT_IOIO:
+ result = vc_handle_ioio(ghcb, ctxt);
+ break;
default:
/*
* Unexpected #VC exception
--
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[PATCH v6 61/76] x86/sev-es: Handle MWAIT/MWAITX Events
From: Tom Lendacky
Implement a handler for #VC exceptions caused by MWAIT and MWAITX
instructions.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: Adapt to #VC handling infrastructure ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-61-j...@8bytes.org
---
arch/x86/kernel/sev-es.c | 10 ++
1 file changed, 10 insertions(+)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index c7324cd0a4d6..76eff9be2510 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -882,6 +882,13 @@ static enum es_result vc_handle_monitor(struct ghcb *ghcb,
return ES_OK;
}
+static enum es_result vc_handle_mwait(struct ghcb *ghcb,
+ struct es_em_ctxt *ctxt)
+{
+ /* Treat the same as MONITOR/MONITORX */
+ return ES_OK;
+}
+
static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
struct ghcb *ghcb,
unsigned long exit_code)
@@ -921,6 +928,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt
*ctxt,
case SVM_EXIT_MONITOR:
result = vc_handle_monitor(ghcb, ctxt);
break;
+ case SVM_EXIT_MWAIT:
+ result = vc_handle_mwait(ghcb, ctxt);
+ break;
case SVM_EXIT_NPF:
result = vc_handle_mmio(ghcb, ctxt);
break;
--
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[PATCH v6 53/76] x86/sev-es: Handle MMIO String Instructions
From: Joerg Roedel
Add handling for emulation the MOVS instruction on MMIO regions, as done
by the memcpy_toio() and memcpy_fromio() functions.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-53-j...@8bytes.org
---
arch/x86/kernel/sev-es.c | 77
1 file changed, 77 insertions(+)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index fa1fa55fd8e3..7bfd402c74e3 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -595,6 +595,73 @@ static enum es_result vc_handle_mmio_twobyte_ops(struct
ghcb *ghcb,
return ret;
}
+/*
+ * The MOVS instruction has two memory operands, which raises the
+ * problem that it is not known whether the access to the source or the
+ * destination caused the #VC exception (and hence whether an MMIO read
+ * or write operation needs to be emulated).
+ *
+ * Instead of playing games with walking page-tables and trying to guess
+ * whether the source or destination is an MMIO range, split the move
+ * into two operations, a read and a write with only one memory operand.
+ * This will cause a nested #VC exception on the MMIO address which can
+ * then be handled.
+ *
+ * This implementation has the benefit that it also supports MOVS where
+ * source _and_ destination are MMIO regions.
+ *
+ * It will slow MOVS on MMIO down a lot, but in SEV-ES guests it is a
+ * rare operation. If it turns out to be a performance problem the split
+ * operations can be moved to memcpy_fromio() and memcpy_toio().
+ */
+static enum es_result vc_handle_mmio_movs(struct es_em_ctxt *ctxt,
+ unsigned int bytes)
+{
+ unsigned long ds_base, es_base;
+ unsigned char *src, *dst;
+ unsigned char buffer[8];
+ enum es_result ret;
+ bool rep;
+ int off;
+
+ ds_base = insn_get_seg_base(ctxt->regs, INAT_SEG_REG_DS);
+ es_base = insn_get_seg_base(ctxt->regs, INAT_SEG_REG_ES);
+
+ if (ds_base == -1L || es_base == -1L) {
+ ctxt->fi.vector = X86_TRAP_GP;
+ ctxt->fi.error_code = 0;
+ return ES_EXCEPTION;
+ }
+
+ src = ds_base + (unsigned char *)ctxt->regs->si;
+ dst = es_base + (unsigned char *)ctxt->regs->di;
+
+ ret = vc_read_mem(ctxt, src, buffer, bytes);
+ if (ret != ES_OK)
+ return ret;
+
+ ret = vc_write_mem(ctxt, dst, buffer, bytes);
+ if (ret != ES_OK)
+ return ret;
+
+ if (ctxt->regs->flags & X86_EFLAGS_DF)
+ off = -bytes;
+ else
+ off = bytes;
+
+ ctxt->regs->si += off;
+ ctxt->regs->di += off;
+
+ rep = insn_has_rep_prefix(>insn);
+ if (rep)
+ ctxt->regs->cx -= 1;
+
+ if (!rep || ctxt->regs->cx == 0)
+ return ES_OK;
+ else
+ return ES_RETRY;
+}
+
static enum es_result vc_handle_mmio(struct ghcb *ghcb,
struct es_em_ctxt *ctxt)
{
@@ -655,6 +722,16 @@ static enum es_result vc_handle_mmio(struct ghcb *ghcb,
memcpy(reg_data, ghcb->shared_buffer, bytes);
break;
+ /* MOVS instruction */
+ case 0xa4:
+ bytes = 1;
+ fallthrough;
+ case 0xa5:
+ if (!bytes)
+ bytes = insn->opnd_bytes;
+
+ ret = vc_handle_mmio_movs(ctxt, bytes);
+ break;
/* Two-Byte Opcodes */
case 0x0f:
ret = vc_handle_mmio_twobyte_ops(ghcb, ctxt);
--
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[PATCH v6 74/76] x86/sev-es: Handle NMI State
From: Joerg Roedel
When running under SEV-ES the kernel has to tell the hypervisor when to
open the NMI window again after an NMI was injected. This is done with
an NMI-complete message to the hypervisor.
Add code to the kernels NMI handler to send this message right at the
beginning of do_nmi(). This always allows nesting NMIs.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-74-j...@8bytes.org
---
arch/x86/include/asm/sev-es.h | 7 +++
arch/x86/include/uapi/asm/svm.h | 1 +
arch/x86/kernel/nmi.c | 6 ++
arch/x86/kernel/sev-es.c| 18 ++
4 files changed, 32 insertions(+)
diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h
index 6ca38dc378e0..21fdee11ac83 100644
--- a/arch/x86/include/asm/sev-es.h
+++ b/arch/x86/include/asm/sev-es.h
@@ -95,10 +95,17 @@ static __always_inline void sev_es_ist_exit(void)
__sev_es_ist_exit();
}
extern int sev_es_setup_ap_jump_table(struct real_mode_header *rmh);
+extern void __sev_es_nmi_complete(void);
+static __always_inline void sev_es_nmi_complete(void)
+{
+ if (static_branch_unlikely(_es_enable_key))
+ __sev_es_nmi_complete();
+}
#else
static inline void sev_es_ist_enter(struct pt_regs *regs) { }
static inline void sev_es_ist_exit(void) { }
static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) {
return 0; }
+static inline void sev_es_nmi_complete(void) { }
#endif
#endif
diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h
index 20a05839dd9a..0f837339db66 100644
--- a/arch/x86/include/uapi/asm/svm.h
+++ b/arch/x86/include/uapi/asm/svm.h
@@ -84,6 +84,7 @@
/* SEV-ES software-defined VMGEXIT events */
#define SVM_VMGEXIT_MMIO_READ 0x8001
#define SVM_VMGEXIT_MMIO_WRITE 0x8002
+#define SVM_VMGEXIT_NMI_COMPLETE 0x8003
#define SVM_VMGEXIT_AP_HLT_LOOP0x8004
#define SVM_VMGEXIT_AP_JUMP_TABLE 0x8005
#defineSVM_VMGEXIT_SET_AP_JUMP_TABLE 0
diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c
index 951f098a4bf5..16ce58c7ed0f 100644
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -478,6 +478,12 @@ DEFINE_IDTENTRY_RAW(exc_nmi)
{
bool irq_state;
+ /*
+* Re-enable NMIs right here when running as an SEV-ES guest. This might
+* cause nested NMIs, but those can be handled safely.
+*/
+ sev_es_nmi_complete();
+
if (IS_ENABLED(CONFIG_SMP) && arch_cpu_is_offline(smp_processor_id()))
return;
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 597ebb73411f..7202d2f5deb8 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -414,6 +414,24 @@ static bool vc_slow_virt_to_phys(struct ghcb *ghcb, struct
es_em_ctxt *ctxt,
/* Include code shared with pre-decompression boot stage */
#include "sev-es-shared.c"
+void __sev_es_nmi_complete(void)
+{
+ struct ghcb_state state;
+ struct ghcb *ghcb;
+
+ ghcb = sev_es_get_ghcb();
+
+ vc_ghcb_invalidate(ghcb);
+ ghcb_set_sw_exit_code(ghcb, SVM_VMGEXIT_NMI_COMPLETE);
+ ghcb_set_sw_exit_info_1(ghcb, 0);
+ ghcb_set_sw_exit_info_2(ghcb, 0);
+
+ sev_es_wr_ghcb_msr(__pa(ghcb));
+ VMGEXIT();
+
+ sev_es_put_ghcb();
+}
+
static u64 sev_es_get_jump_table_addr(void)
{
struct ghcb_state state;
--
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[PATCH v6 72/76] x86/head/64: Rename start_cpu0
From: Joerg Roedel
For SEV-ES this entry point will be used for restarting APs after they
have been offlined. Remove the '0' from the name to reflect that.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-72-j...@8bytes.org
---
arch/x86/include/asm/cpu.h | 2 +-
arch/x86/kernel/head_32.S | 4 ++--
arch/x86/kernel/head_64.S | 6 +++---
arch/x86/kernel/smpboot.c | 4 ++--
4 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index da78ccbd493b..1536b607971f 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -29,7 +29,7 @@ struct x86_cpu {
#ifdef CONFIG_HOTPLUG_CPU
extern int arch_register_cpu(int num);
extern void arch_unregister_cpu(int);
-extern void start_cpu0(void);
+extern void start_cpu(void);
#ifdef CONFIG_DEBUG_HOTPLUG_CPU0
extern int _debug_hotplug_cpu(int cpu, int action);
#endif
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index 7ed84c282233..f63e1b7f4141 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -143,12 +143,12 @@ SYM_CODE_END(startup_32)
* up already except stack. We just set up stack here. Then call
* start_secondary().
*/
-SYM_FUNC_START(start_cpu0)
+SYM_FUNC_START(start_cpu)
movl initial_stack, %ecx
movl %ecx, %esp
call *(initial_code)
1: jmp 1b
-SYM_FUNC_END(start_cpu0)
+SYM_FUNC_END(start_cpu)
#endif
/*
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index a708107688a2..352311c5d8d1 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -309,15 +309,15 @@ SYM_CODE_END(secondary_startup_64)
#ifdef CONFIG_HOTPLUG_CPU
/*
- * Boot CPU0 entry point. It's called from play_dead(). Everything has been set
+ * CPU entry point. It's called from play_dead(). Everything has been set
* up already except stack. We just set up stack here. Then call
* start_secondary() via .Ljump_to_C_code.
*/
-SYM_CODE_START(start_cpu0)
+SYM_CODE_START(start_cpu)
UNWIND_HINT_EMPTY
movqinitial_stack(%rip), %rsp
jmp .Ljump_to_C_code
-SYM_CODE_END(start_cpu0)
+SYM_CODE_END(start_cpu)
#endif
/* Both SMP bootup and ACPI suspend change these variables */
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index fb55d28332e2..c6311c55b84c 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -1726,7 +1726,7 @@ static inline void mwait_play_dead(void)
* If NMI wants to wake up CPU0, start CPU0.
*/
if (wakeup_cpu0())
- start_cpu0();
+ start_cpu();
}
}
@@ -1741,7 +1741,7 @@ void hlt_play_dead(void)
* If NMI wants to wake up CPU0, start CPU0.
*/
if (wakeup_cpu0())
- start_cpu0();
+ start_cpu();
}
}
--
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[PATCH v6 65/76] x86/paravirt: Allow hypervisor specific VMMCALL handling under SEV-ES
From: Joerg Roedel
Add two new paravirt callbacks to provide hypervisor specific processor
state in the GHCB and to copy state from the hypervisor back to the
processor.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-65-j...@8bytes.org
---
arch/x86/include/asm/x86_init.h | 16 +++-
arch/x86/kernel/sev-es.c| 12
2 files changed, 27 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index 6807153c0410..0304e2931cd3 100644
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -4,8 +4,10 @@
#include
+struct ghcb;
struct mpc_bus;
struct mpc_cpu;
+struct pt_regs;
struct mpc_table;
struct cpuinfo_x86;
@@ -236,10 +238,22 @@ struct x86_legacy_features {
/**
* struct x86_hyper_runtime - x86 hypervisor specific runtime callbacks
*
- * @pin_vcpu: pin current vcpu to specified physical cpu (run rarely)
+ * @pin_vcpu: pin current vcpu to specified physical
+ * cpu (run rarely)
+ * @sev_es_hcall_prepare: Load additional hypervisor-specific
+ * state into the GHCB when doing a VMMCALL under
+ * SEV-ES. Called from the #VC exception handler.
+ * @sev_es_hcall_finish: Copies state from the GHCB back into the
+ * processor (or pt_regs). Also runs checks on the
+ * state returned from the hypervisor after a
+ * VMMCALL under SEV-ES. Needs to return 'false'
+ * if the checks fail. Called from the #VC
+ * exception handler.
*/
struct x86_hyper_runtime {
void (*pin_vcpu)(int cpu);
+ void (*sev_es_hcall_prepare)(struct ghcb *ghcb, struct pt_regs *regs);
+ bool (*sev_es_hcall_finish)(struct ghcb *ghcb, struct pt_regs *regs);
};
/**
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index e1f3ebbcc122..28fe95ecd508 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -897,6 +897,9 @@ static enum es_result vc_handle_vmmcall(struct ghcb *ghcb,
ghcb_set_rax(ghcb, ctxt->regs->ax);
ghcb_set_cpl(ghcb, user_mode(ctxt->regs) ? 3 : 0);
+ if (x86_platform.hyper.sev_es_hcall_prepare)
+ x86_platform.hyper.sev_es_hcall_prepare(ghcb, ctxt->regs);
+
ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_VMMCALL, 0, 0);
if (ret != ES_OK)
return ret;
@@ -906,6 +909,15 @@ static enum es_result vc_handle_vmmcall(struct ghcb *ghcb,
ctxt->regs->ax = ghcb->save.rax;
+ /*
+* Call sev_es_hcall_finish() after regs->ax is already set.
+* This allows the hypervisor handler to overwrite it again if
+* necessary.
+*/
+ if (x86_platform.hyper.sev_es_hcall_finish &&
+ !x86_platform.hyper.sev_es_hcall_finish(ghcb, ctxt->regs))
+ return ES_VMM_ERROR;
+
return ES_OK;
}
--
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[PATCH v6 66/76] x86/kvm: Add KVM specific VMMCALL handling under SEV-ES
From: Tom Lendacky
Implement the callbacks to copy the processor state required by KVM to
the GHCB.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: - Split out of a larger patch
- Adapt to different callback functions ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-66-j...@8bytes.org
---
arch/x86/kernel/kvm.c | 35 +--
1 file changed, 29 insertions(+), 6 deletions(-)
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 08320b0b2b27..0f9597275e9c 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -36,6 +36,8 @@
#include
#include
#include
+#include
+#include
DEFINE_STATIC_KEY_FALSE(kvm_async_pf_enabled);
@@ -746,13 +748,34 @@ static void __init kvm_init_platform(void)
x86_platform.apic_post_init = kvm_apic_init;
}
+#if defined(CONFIG_AMD_MEM_ENCRYPT)
+static void kvm_sev_es_hcall_prepare(struct ghcb *ghcb, struct pt_regs *regs)
+{
+ /* RAX and CPL are already in the GHCB */
+ ghcb_set_rbx(ghcb, regs->bx);
+ ghcb_set_rcx(ghcb, regs->cx);
+ ghcb_set_rdx(ghcb, regs->dx);
+ ghcb_set_rsi(ghcb, regs->si);
+}
+
+static bool kvm_sev_es_hcall_finish(struct ghcb *ghcb, struct pt_regs *regs)
+{
+ /* No checking of the return state needed */
+ return true;
+}
+#endif
+
const __initconst struct hypervisor_x86 x86_hyper_kvm = {
- .name = "KVM",
- .detect = kvm_detect,
- .type = X86_HYPER_KVM,
- .init.guest_late_init = kvm_guest_init,
- .init.x2apic_available = kvm_para_available,
- .init.init_platform = kvm_init_platform,
+ .name = "KVM",
+ .detect = kvm_detect,
+ .type = X86_HYPER_KVM,
+ .init.guest_late_init = kvm_guest_init,
+ .init.x2apic_available = kvm_para_available,
+ .init.init_platform = kvm_init_platform,
+#if defined(CONFIG_AMD_MEM_ENCRYPT)
+ .runtime.sev_es_hcall_prepare = kvm_sev_es_hcall_prepare,
+ .runtime.sev_es_hcall_finish= kvm_sev_es_hcall_finish,
+#endif
};
static __init int activate_jump_labels(void)
--
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[PATCH v6 47/76] x86/dumpstack/64: Add noinstr version of get_stack_info()
From: Joerg Roedel
The get_stack_info functionality is needed in the entry code for the #VC
exception handler. Provide a version of it in the .text.noinstr
section which can be called safely from there.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-47-j...@8bytes.org
---
arch/x86/include/asm/stacktrace.h | 2 ++
arch/x86/kernel/dumpstack.c | 7 +++---
arch/x86/kernel/dumpstack_64.c| 39 ++-
arch/x86/mm/cpu_entry_area.c | 3 ++-
4 files changed, 31 insertions(+), 20 deletions(-)
diff --git a/arch/x86/include/asm/stacktrace.h
b/arch/x86/include/asm/stacktrace.h
index 5ae5a68e469d..49600643faba 100644
--- a/arch/x86/include/asm/stacktrace.h
+++ b/arch/x86/include/asm/stacktrace.h
@@ -35,6 +35,8 @@ bool in_entry_stack(unsigned long *stack, struct stack_info
*info);
int get_stack_info(unsigned long *stack, struct task_struct *task,
struct stack_info *info, unsigned long *visit_mask);
+bool get_stack_info_noinstr(unsigned long *stack, struct task_struct *task,
+ struct stack_info *info);
const char *stack_type_name(enum stack_type type);
diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c
index 48ce44576947..74147f7b3d82 100644
--- a/arch/x86/kernel/dumpstack.c
+++ b/arch/x86/kernel/dumpstack.c
@@ -29,8 +29,8 @@ static int die_counter;
static struct pt_regs exec_summary_regs;
-bool in_task_stack(unsigned long *stack, struct task_struct *task,
- struct stack_info *info)
+bool noinstr in_task_stack(unsigned long *stack, struct task_struct *task,
+ struct stack_info *info)
{
unsigned long *begin = task_stack_page(task);
unsigned long *end = task_stack_page(task) + THREAD_SIZE;
@@ -46,7 +46,8 @@ bool in_task_stack(unsigned long *stack, struct task_struct
*task,
return true;
}
-bool in_entry_stack(unsigned long *stack, struct stack_info *info)
+/* Called from get_stack_info_noinstr - so must be noinstr too */
+bool noinstr in_entry_stack(unsigned long *stack, struct stack_info *info)
{
struct entry_stack *ss = cpu_entry_stack(smp_processor_id());
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index c49cf594714b..5a85730eb0ca 100644
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -85,7 +85,7 @@ struct estack_pages estack_pages[CEA_ESTACK_PAGES]
cacheline_aligned = {
EPAGERANGE(VC2),
};
-static bool in_exception_stack(unsigned long *stack, struct stack_info *info)
+static bool __always_inline in_exception_stack(unsigned long *stack, struct
stack_info *info)
{
unsigned long begin, end, stk = (unsigned long)stack;
const struct estack_pages *ep;
@@ -126,7 +126,7 @@ static bool in_exception_stack(unsigned long *stack, struct
stack_info *info)
return true;
}
-static bool in_irq_stack(unsigned long *stack, struct stack_info *info)
+static bool __always_inline in_irq_stack(unsigned long *stack, struct
stack_info *info)
{
unsigned long *end = (unsigned long
*)this_cpu_read(hardirq_stack_ptr);
unsigned long *begin = end - (IRQ_STACK_SIZE / sizeof(long));
@@ -151,32 +151,38 @@ static bool in_irq_stack(unsigned long *stack, struct
stack_info *info)
return true;
}
-int get_stack_info(unsigned long *stack, struct task_struct *task,
- struct stack_info *info, unsigned long *visit_mask)
+bool noinstr get_stack_info_noinstr(unsigned long *stack, struct task_struct
*task,
+ struct stack_info *info)
{
- if (!stack)
- goto unknown;
-
- task = task ? : current;
-
if (in_task_stack(stack, task, info))
- goto recursion_check;
+ return true;
if (task != current)
- goto unknown;
+ return false;
if (in_exception_stack(stack, info))
- goto recursion_check;
+ return true;
if (in_irq_stack(stack, info))
- goto recursion_check;
+ return true;
if (in_entry_stack(stack, info))
- goto recursion_check;
+ return true;
- goto unknown;
+ return false;
+}
+
+int get_stack_info(unsigned long *stack, struct task_struct *task,
+ struct stack_info *info, unsigned long *visit_mask)
+{
+ task = task ? : current;
+
+ if (!stack)
+ goto unknown;
+
+ if (!get_stack_info_noinstr(stack, task, info))
+ goto unknown;
-recursion_check:
/*
* Make sure we don't iterate through any given stack more than once.
* If it comes up a second time then there's something wrong going on:
@@ -196,4 +202,5 @@ int get_stack_info(unsigned long *stack, struct task_struct
*task,
unknown:
info->type = STACK_TYPE_UNKNOWN;
[PATCH v6 57/76] x86/sev-es: Handle RDTSC(P) Events
From: Tom Lendacky
Implement a handler for #VC exceptions caused by RDTSC and RDTSCP
instructions. Also make it available in the pre-decompression stage
because the KASLR code used RDTSC/RDTSCP to gather entropy and some
hypervisors intercept these instructions.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: - Adapt to #VC handling infrastructure
- Make it available early ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-57-j...@8bytes.org
---
arch/x86/boot/compressed/sev-es.c | 4
arch/x86/kernel/sev-es-shared.c | 23 +++
arch/x86/kernel/sev-es.c | 4
3 files changed, 31 insertions(+)
diff --git a/arch/x86/boot/compressed/sev-es.c
b/arch/x86/boot/compressed/sev-es.c
index 851d7af29d79..1ce144e0ddc3 100644
--- a/arch/x86/boot/compressed/sev-es.c
+++ b/arch/x86/boot/compressed/sev-es.c
@@ -181,6 +181,10 @@ void do_boot_stage2_vc(struct pt_regs *regs, unsigned long
exit_code)
goto finish;
switch (exit_code) {
+ case SVM_EXIT_RDTSC:
+ case SVM_EXIT_RDTSCP:
+ result = vc_handle_rdtsc(boot_ghcb, , exit_code);
+ break;
case SVM_EXIT_IOIO:
result = vc_handle_ioio(boot_ghcb, );
break;
diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c
index a6b41910b8ab..92d77b725ccb 100644
--- a/arch/x86/kernel/sev-es-shared.c
+++ b/arch/x86/kernel/sev-es-shared.c
@@ -467,3 +467,26 @@ static enum es_result vc_handle_cpuid(struct ghcb *ghcb,
return ES_OK;
}
+
+static enum es_result vc_handle_rdtsc(struct ghcb *ghcb,
+ struct es_em_ctxt *ctxt,
+ unsigned long exit_code)
+{
+ bool rdtscp = (exit_code == SVM_EXIT_RDTSCP);
+ enum es_result ret;
+
+ ret = sev_es_ghcb_hv_call(ghcb, ctxt, exit_code, 0, 0);
+ if (ret != ES_OK)
+ return ret;
+
+ if (!(ghcb_rax_is_valid(ghcb) && ghcb_rdx_is_valid(ghcb) &&
+(!rdtscp || ghcb_rcx_is_valid(ghcb
+ return ES_VMM_ERROR;
+
+ ctxt->regs->ax = ghcb->save.rax;
+ ctxt->regs->dx = ghcb->save.rdx;
+ if (rdtscp)
+ ctxt->regs->cx = ghcb->save.rcx;
+
+ return ES_OK;
+}
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 2e83bbc330c9..0d8103a87ff1 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -866,6 +866,10 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt
*ctxt,
case SVM_EXIT_WRITE_DR7:
result = vc_handle_dr7_write(ghcb, ctxt);
break;
+ case SVM_EXIT_RDTSC:
+ case SVM_EXIT_RDTSCP:
+ result = vc_handle_rdtsc(ghcb, ctxt, exit_code);
+ break;
case SVM_EXIT_CPUID:
result = vc_handle_cpuid(ghcb, ctxt);
break;
--
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[PATCH v6 46/76] x86/sev-es: Adjust #VC IST Stack on entering NMI handler
From: Joerg Roedel
When an NMI hits in the #VC handler entry code before it switched to
another stack, any subsequent #VC exception in the NMI code-path will
overwrite the interrupted #VC handlers stack.
Make sure this doesn't happen by explicitly adjusting the #VC IST entry
in the NMI handler for the time in can cause #VC exceptions.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-46-j...@8bytes.org
---
arch/x86/include/asm/sev-es.h | 19 +++
arch/x86/kernel/nmi.c | 6
arch/x86/kernel/sev-es.c | 59 +++
arch/x86/kernel/traps.c | 2 ++
4 files changed, 86 insertions(+)
diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h
index 824e9e6b067c..2dd19932a60d 100644
--- a/arch/x86/include/asm/sev-es.h
+++ b/arch/x86/include/asm/sev-es.h
@@ -77,4 +77,23 @@ static inline u64 lower_bits(u64 val, unsigned int bits)
extern void vc_no_ghcb(void);
extern bool handle_vc_boot_ghcb(struct pt_regs *regs);
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+extern struct static_key_false sev_es_enable_key;
+extern void __sev_es_ist_enter(struct pt_regs *regs);
+extern void __sev_es_ist_exit(void);
+static __always_inline void sev_es_ist_enter(struct pt_regs *regs)
+{
+ if (static_branch_unlikely(_es_enable_key))
+ __sev_es_ist_enter(regs);
+}
+static __always_inline void sev_es_ist_exit(void)
+{
+ if (static_branch_unlikely(_es_enable_key))
+ __sev_es_ist_exit();
+}
+#else
+static inline void sev_es_ist_enter(struct pt_regs *regs) { }
+static inline void sev_es_ist_exit(void) { }
+#endif
+
#endif
diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c
index 4fc9954a9560..951f098a4bf5 100644
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -33,6 +33,7 @@
#include
#include
#include
+#include
#define CREATE_TRACE_POINTS
#include
@@ -488,6 +489,9 @@ DEFINE_IDTENTRY_RAW(exc_nmi)
this_cpu_write(nmi_cr2, read_cr2());
nmi_restart:
+ /* Needs to happen before DR7 is accessed */
+ sev_es_ist_enter(regs);
+
this_cpu_write(nmi_dr7, local_db_save());
irq_state = idtentry_enter_nmi(regs);
@@ -501,6 +505,8 @@ DEFINE_IDTENTRY_RAW(exc_nmi)
local_db_restore(this_cpu_read(nmi_dr7));
+ sev_es_ist_exit();
+
if (unlikely(this_cpu_read(nmi_cr2) != read_cr2()))
write_cr2(this_cpu_read(nmi_cr2));
if (this_cpu_dec_return(nmi_state))
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 64002d86a237..95831d103418 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -52,6 +52,9 @@ struct sev_es_runtime_data {
static DEFINE_PER_CPU(struct sev_es_runtime_data*, runtime_data);
+DEFINE_STATIC_KEY_FALSE(sev_es_enable_key);
+EXPORT_SYMBOL_GPL(sev_es_enable_key);
+
static void __init sev_es_setup_vc_stacks(int cpu)
{
struct sev_es_runtime_data *data;
@@ -73,6 +76,59 @@ static void __init sev_es_setup_vc_stacks(int cpu)
cea_set_pte((void *)vaddr, pa, PAGE_KERNEL);
}
+static __always_inline bool on_vc_stack(unsigned long sp)
+{
+ return ((sp >= __this_cpu_ist_bot_va(VC)) && (sp <
__this_cpu_ist_top_va(VC)));
+}
+
+/*
+ * This function handles the case when an NM is raised in the #VC exception
+ * handler entry code. In this case the IST entry for VC must be adjusted, so
+ * that any subsequent VC exception will not overwrite the stack contents of
the
+ * interrupted VC handler.
+ *
+ * The IST entry is adjusted unconditionally so that it can be also be
+ * unconditionally back-adjusted in sev_es_ist_exit(). Otherwise a nested
+ * sev_es_ist_exit() call may back-adjust the IST entry too early.
+ */
+void noinstr __sev_es_ist_enter(struct pt_regs *regs)
+{
+ unsigned long old_ist, new_ist;
+ unsigned long *p;
+
+ /* Read old IST entry */
+ old_ist = __this_cpu_read(cpu_tss_rw.x86_tss.ist[IST_INDEX_VC]);
+
+ /* Make room on the IST stack */
+ if (on_vc_stack(regs->sp))
+ new_ist = ALIGN_DOWN(regs->sp, 8) - sizeof(old_ist);
+ else
+ new_ist = old_ist - sizeof(old_ist);
+
+ /* Store old IST entry */
+ p = (unsigned long *)new_ist;
+ *p = old_ist;
+
+ /* Set new IST entry */
+ this_cpu_write(cpu_tss_rw.x86_tss.ist[IST_INDEX_VC], new_ist);
+}
+
+void noinstr __sev_es_ist_exit(void)
+{
+ unsigned long ist;
+ unsigned long *p;
+
+ /* Read IST entry */
+ ist = __this_cpu_read(cpu_tss_rw.x86_tss.ist[IST_INDEX_VC]);
+
+ if (WARN_ON(ist == __this_cpu_ist_top_va(VC)))
+ return;
+
+ /* Read back old IST entry and write it to the TSS */
+ p = (unsigned long *)ist;
+ this_cpu_write(cpu_tss_rw.x86_tss.ist[IST_INDEX_VC], *p);
+}
+
/* Needed in vc_early_forward_exception */
void do_early_exception(struct pt_regs *regs, int trapnr);
@@ -277,6 +333,9 @@ void __init
[PATCH v6 59/76] x86/sev-es: Handle INVD Events
From: Tom Lendacky
Implement a handler for #VC exceptions caused by INVD instructions.
Since Linux should never use INVD, just mark it as unsupported.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: Adapt to #VC handling infrastructure ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-59-j...@8bytes.org
---
arch/x86/kernel/sev-es.c | 4
1 file changed, 4 insertions(+)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index e098d1e71a3e..4e1989c58df8 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -892,6 +892,10 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt
*ctxt,
case SVM_EXIT_RDPMC:
result = vc_handle_rdpmc(ghcb, ctxt);
break;
+ case SVM_EXIT_INVD:
+ pr_err_ratelimited("#VC exception for INVD??? Seriously???\n");
+ result = ES_UNSUPPORTED;
+ break;
case SVM_EXIT_CPUID:
result = vc_handle_cpuid(ghcb, ctxt);
break;
--
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[PATCH v6 68/76] x86/realmode: Add SEV-ES specific trampoline entry point
From: Joerg Roedel
The code at the trampoline entry point is executed in real-mode. In
real-mode #VC exceptions can't be handled, so anything that might cause
such an exception must be avoided.
In the standard trampoline entry code this is the WBINVD instruction and
the call to verify_cpu(), which are both not needed anyway when running
as an SEV-ES guest.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-68-j...@8bytes.org
---
arch/x86/include/asm/realmode.h | 3 +++
arch/x86/realmode/rm/header.S| 3 +++
arch/x86/realmode/rm/trampoline_64.S | 20
3 files changed, 26 insertions(+)
diff --git a/arch/x86/include/asm/realmode.h b/arch/x86/include/asm/realmode.h
index b35030eeec36..6590394af309 100644
--- a/arch/x86/include/asm/realmode.h
+++ b/arch/x86/include/asm/realmode.h
@@ -21,6 +21,9 @@ struct real_mode_header {
/* SMP trampoline */
u32 trampoline_start;
u32 trampoline_header;
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+ u32 sev_es_trampoline_start;
+#endif
#ifdef CONFIG_X86_64
u32 trampoline_pgd;
#endif
diff --git a/arch/x86/realmode/rm/header.S b/arch/x86/realmode/rm/header.S
index af04512c02d9..8c1db5bf5d78 100644
--- a/arch/x86/realmode/rm/header.S
+++ b/arch/x86/realmode/rm/header.S
@@ -20,6 +20,9 @@ SYM_DATA_START(real_mode_header)
/* SMP trampoline */
.long pa_trampoline_start
.long pa_trampoline_header
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+ .long pa_sev_es_trampoline_start
+#endif
#ifdef CONFIG_X86_64
.long pa_trampoline_pgd;
#endif
diff --git a/arch/x86/realmode/rm/trampoline_64.S
b/arch/x86/realmode/rm/trampoline_64.S
index 251758ed7443..84c5d1b33d10 100644
--- a/arch/x86/realmode/rm/trampoline_64.S
+++ b/arch/x86/realmode/rm/trampoline_64.S
@@ -56,6 +56,7 @@ SYM_CODE_START(trampoline_start)
testl %eax, %eax # Check for return code
jnz no_longmode
+.Lswitch_to_protected:
/*
* GDT tables in non default location kernel can be beyond 16MB and
* lgdt will not be able to load the address as in real mode default
@@ -80,6 +81,25 @@ no_longmode:
jmp no_longmode
SYM_CODE_END(trampoline_start)
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+/* SEV-ES supports non-zero IP for entry points - no alignment needed */
+SYM_CODE_START(sev_es_trampoline_start)
+ cli # We should be safe anyway
+
+ LJMPW_RM(1f)
+1:
+ mov %cs, %ax# Code and data in the same place
+ mov %ax, %ds
+ mov %ax, %es
+ mov %ax, %ss
+
+ # Setup stack
+ movl$rm_stack_end, %esp
+
+ jmp .Lswitch_to_protected
+SYM_CODE_END(sev_es_trampoline_start)
+#endif /* CONFIG_AMD_MEM_ENCRYPT */
+
#include "../kernel/verify_cpu.S"
.section ".text32","ax"
--
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[PATCH v6 48/76] x86/entry/64: Add entry code for #VC handler
From: Joerg Roedel The #VC handler needs special entry code because: 1. It runs on an IST stack 2. It needs to be able to handle nested #VC exceptions To make this work the entry code is implemented to pretend it doesn't use an IST stack. When entered from user-mode or early SYSCALL entry path it switches to the task stack, if entered from kernel-mode it tries to switch back to the previous stack in the IRET frame. The stack found in the IRET frame is validated first, and if it is not safe to use it for the #VC handler, the code will switch to a fall-back stack (the #VC2 IST stack). From there it can cause nested exceptions again. Signed-off-by: Joerg Roedel Link: https://lore.kernel.org/r/20200724160336.5435-48-j...@8bytes.org --- arch/x86/entry/entry_64.S | 78 + arch/x86/include/asm/idtentry.h | 44 +++ arch/x86/include/asm/proto.h| 1 + arch/x86/include/asm/traps.h| 1 + arch/x86/kernel/traps.c | 51 + 5 files changed, 175 insertions(+) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 26fc9b42fadc..cc054568ad3f 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -101,6 +101,8 @@ SYM_CODE_START(entry_SYSCALL_64) SWITCH_TO_KERNEL_CR3 scratch_reg=%rsp movqPER_CPU_VAR(cpu_current_top_of_stack), %rsp +SYM_INNER_LABEL(entry_SYSCALL_64_safe_stack, SYM_L_GLOBAL) + /* Construct struct pt_regs on stack */ pushq $__USER_DS /* pt_regs->ss */ pushq PER_CPU_VAR(cpu_tss_rw + TSS_sp2) /* pt_regs->sp */ @@ -446,6 +448,82 @@ _ASM_NOKPROBE(\asmsym) SYM_CODE_END(\asmsym) .endm +/** + * idtentry_vc - Macro to generate entry stub for #VC + * @vector:Vector number + * @asmsym:ASM symbol for the entry point + * @cfunc: C function to be called + * + * The macro emits code to set up the kernel context for #VC. The #VC handler + * runs on an IST stack and needs to be able to cause nested #VC exceptions. + * + * To make this work the #VC entry code tries its best to pretend it doesn't use + * an IST stack by switching to the task stack if coming from user-space (which + * includes early SYSCALL entry path) or back to the stack in the IRET frame if + * entered from kernel-mode. + * + * If entered from kernel-mode the return stack is validated first, and if it is + * not safe to use (e.g. because it points to the entry stack) the #VC handler + * will switch to a fall-back stack (VC2) and call a special handler function. + * + * The macro is only used for one vector, but it is planned to extend it in the + * future for the #HV exception. + */ +.macro idtentry_vc vector asmsym cfunc +SYM_CODE_START(\asmsym) + UNWIND_HINT_IRET_REGS + ASM_CLAC + + /* +* If the entry is from userspace, switch stacks and treat it as +* a normal entry. +*/ + testb $3, CS-ORIG_RAX(%rsp) + jnz .Lfrom_usermode_switch_stack_\@ + + /* +* paranoid_entry returns SWAPGS flag for paranoid_exit in EBX. +* EBX == 0 -> SWAPGS, EBX == 1 -> no SWAPGS +*/ + callparanoid_entry + + UNWIND_HINT_REGS + + /* +* Switch off the IST stack to make it free for nested exceptions. The +* vc_switch_off_ist() function will switch back to the interrupted +* stack if it is safe to do so. If not it switches to the VC fall-back +* stack. +*/ + movq%rsp, %rdi /* pt_regs pointer */ + callvc_switch_off_ist + movq%rax, %rsp /* Switch to new stack */ + + UNWIND_HINT_REGS + + /* Update pt_regs */ + movqORIG_RAX(%rsp), %rsi/* get error code into 2nd argument*/ + movq$-1, ORIG_RAX(%rsp) /* no syscall to restart */ + + movq%rsp, %rdi /* pt_regs pointer */ + + call\cfunc + + /* +* No need to switch back to the IST stack. The current stack is either +* identical to the stack in the IRET frame or the VC fall-back stack, +* so it is definitly mapped even with PTI enabled. +*/ + jmp paranoid_exit + + /* Switch to the regular task stack */ +.Lfrom_usermode_switch_stack_\@: + idtentry_body safe_stack_\cfunc, has_error_code=1 + +_ASM_NOKPROBE(\asmsym) +SYM_CODE_END(\asmsym) +.endm + /* * Double fault entry. Straight paranoid. No checks from which context * this comes because for the espfix induced #DF this would do the wrong diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index 337dcfd45472..5ce67113a761 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -308,6 +308,18 @@ static __always_inline void __##func(struct pt_regs *regs) DECLARE_IDTENTRY_RAW(vector, func); \
[PATCH v6 75/76] x86/efi: Add GHCB mappings when SEV-ES is active
From: Tom Lendacky
Calling down to EFI runtime services can result in the firmware performing
VMGEXIT calls. The firmware is likely to use the GHCB of the OS (e.g., for
setting EFI variables), so each GHCB in the system needs to be identity
mapped in the EFI page tables, as unencrypted, to avoid page faults.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: Moved GHCB mapping loop to sev-es.c ]
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-75-j...@8bytes.org
---
arch/x86/boot/compressed/sev-es.c | 1 +
arch/x86/include/asm/sev-es.h | 2 ++
arch/x86/kernel/sev-es.c | 30 ++
arch/x86/platform/efi/efi_64.c| 10 ++
4 files changed, 43 insertions(+)
diff --git a/arch/x86/boot/compressed/sev-es.c
b/arch/x86/boot/compressed/sev-es.c
index 1ce144e0ddc3..b522c18c0588 100644
--- a/arch/x86/boot/compressed/sev-es.c
+++ b/arch/x86/boot/compressed/sev-es.c
@@ -12,6 +12,7 @@
*/
#include "misc.h"
+#include
#include
#include
#include
diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h
index 21fdee11ac83..f22c4531624c 100644
--- a/arch/x86/include/asm/sev-es.h
+++ b/arch/x86/include/asm/sev-es.h
@@ -101,11 +101,13 @@ static __always_inline void sev_es_nmi_complete(void)
if (static_branch_unlikely(_es_enable_key))
__sev_es_nmi_complete();
}
+extern int __init sev_es_efi_map_ghcbs(pgd_t *pgd);
#else
static inline void sev_es_ist_enter(struct pt_regs *regs) { }
static inline void sev_es_ist_exit(void) { }
static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) {
return 0; }
static inline void sev_es_nmi_complete(void) { }
+static inline int sev_es_efi_map_ghcbs(pgd_t *pgd) { return 0; }
#endif
#endif
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 7202d2f5deb8..2d73f5abe04b 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -495,6 +495,36 @@ int sev_es_setup_ap_jump_table(struct real_mode_header
*rmh)
return 0;
}
+/*
+ * This is needed by the OVMF UEFI firmware which will use whatever it finds in
+ * the GHCB MSR as its GHCB to talk to the hypervisor. So make sure the per-cpu
+ * runtime GHCBs used by the kernel are also mapped in the EFI page-table.
+ */
+int __init sev_es_efi_map_ghcbs(pgd_t *pgd)
+{
+ struct sev_es_runtime_data *data;
+ unsigned long address, pflags;
+ int cpu;
+ u64 pfn;
+
+ if (!sev_es_active())
+ return 0;
+
+ pflags = _PAGE_NX | _PAGE_RW;
+
+ for_each_possible_cpu(cpu) {
+ data = per_cpu(runtime_data, cpu);
+
+ address = __pa(>ghcb_page);
+ pfn = address >> PAGE_SHIFT;
+
+ if (kernel_map_pages_in_pgd(pgd, pfn, address, 1, pflags))
+ return 1;
+ }
+
+ return 0;
+}
+
static enum es_result vc_handle_msr(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
{
struct pt_regs *regs = ctxt->regs;
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 6af4da1149ba..8f5759df7776 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -47,6 +47,7 @@
#include
#include
#include
+#include
/*
* We allocate runtime services regions top-down, starting from -4G, i.e.
@@ -229,6 +230,15 @@ int __init efi_setup_page_tables(unsigned long pa_memmap,
unsigned num_pages)
return 1;
}
+ /*
+* When SEV-ES is active, the GHCB as set by the kernel will be used
+* by firmware. Create a 1:1 unencrypted mapping for each GHCB.
+*/
+ if (sev_es_efi_map_ghcbs(pgd)) {
+ pr_err("Failed to create 1:1 mapping for the GHCBs!\n");
+ return 1;
+ }
+
/*
* When making calls to the firmware everything needs to be 1:1
* mapped and addressable with 32-bit pointers. Map the kernel
--
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[PATCH v6 56/76] x86/sev-es: Handle WBINVD Events
From: Tom Lendacky
Implement a handler for #VC exceptions caused by WBINVD instructions.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: Adapt to #VC handling framework ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-56-j...@8bytes.org
---
arch/x86/kernel/sev-es.c | 9 +
1 file changed, 9 insertions(+)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 1a7bfcb37602..2e83bbc330c9 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -847,6 +847,12 @@ static enum es_result vc_handle_dr7_read(struct ghcb *ghcb,
return ES_OK;
}
+static enum es_result vc_handle_wbinvd(struct ghcb *ghcb,
+ struct es_em_ctxt *ctxt)
+{
+ return sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_WBINVD, 0, 0);
+}
+
static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
struct ghcb *ghcb,
unsigned long exit_code)
@@ -869,6 +875,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt
*ctxt,
case SVM_EXIT_MSR:
result = vc_handle_msr(ghcb, ctxt);
break;
+ case SVM_EXIT_WBINVD:
+ result = vc_handle_wbinvd(ghcb, ctxt);
+ break;
case SVM_EXIT_NPF:
result = vc_handle_mmio(ghcb, ctxt);
break;
--
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[PATCH v6 70/76] x86/smpboot: Setup TSS for starting AP
From: Joerg Roedel
Set up the TSS for starting APs before they are kicked. This allows the
APs to use IST in early exception handling.
Also load the TSS early if the TSS entry in the GDT is present. This
makes sure a TSS is only loaded when it has been set up.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-70-j...@8bytes.org
---
arch/x86/include/asm/processor.h | 7 ++
arch/x86/include/asm/setup.h | 1 +
arch/x86/kernel/cpu/common.c | 37 +++-
arch/x86/kernel/head64.c | 11 ++
arch/x86/kernel/head_64.S| 5 +
arch/x86/kernel/smpboot.c| 6 ++
6 files changed, 52 insertions(+), 15 deletions(-)
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 97143d87994c..2cc72d583003 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -697,6 +697,13 @@ extern void load_fixmap_gdt(int);
extern void load_percpu_segment(int);
extern void cpu_init(void);
extern void cr4_init(void);
+extern void tss_setup(int cpu);
+
+#ifdef CONFIG_X86_64
+extern void setup_getcpu(int cpu);
+#else
+static inline void setup_getcpu(int cpu) { }
+#endif
static inline unsigned long get_debugctlmsr(void)
{
diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h
index 0ce6453c9272..bbd40dd20be7 100644
--- a/arch/x86/include/asm/setup.h
+++ b/arch/x86/include/asm/setup.h
@@ -54,6 +54,7 @@ extern void startup_64_setup_env(unsigned long physbase);
extern void early_idt_setup_early_handler(unsigned long physaddr);
extern void early_load_idt(void);
extern void early_idt_setup(unsigned long physbase);
+extern void early_load_tss(void);
extern void __init do_early_exception(struct pt_regs *regs, int trapnr);
#ifdef CONFIG_X86_INTEL_MID
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 1d65365363a1..f98efb6f988f 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1787,7 +1787,7 @@ static void wait_for_master_cpu(int cpu)
}
#ifdef CONFIG_X86_64
-static inline void setup_getcpu(int cpu)
+void setup_getcpu(int cpu)
{
unsigned long cpudata = vdso_encode_cpunode(cpu,
early_cpu_to_node(cpu));
struct desc_struct d = { };
@@ -1814,27 +1814,26 @@ static inline void ucode_cpu_init(int cpu)
load_ucode_ap();
}
-static inline void tss_setup_ist(struct tss_struct *tss)
+static inline void tss_setup_ist(struct tss_struct *tss,
+struct cpu_entry_area *cea)
{
/* Set up the per-CPU TSS IST stacks */
- tss->x86_tss.ist[IST_INDEX_DF] = __this_cpu_ist_top_va(DF);
- tss->x86_tss.ist[IST_INDEX_NMI] = __this_cpu_ist_top_va(NMI);
- tss->x86_tss.ist[IST_INDEX_DB] = __this_cpu_ist_top_va(DB);
- tss->x86_tss.ist[IST_INDEX_MCE] = __this_cpu_ist_top_va(MCE);
+ tss->x86_tss.ist[IST_INDEX_DF] = CEA_ESTACK_TOP(>estacks, DF);
+ tss->x86_tss.ist[IST_INDEX_NMI] = CEA_ESTACK_TOP(>estacks, NMI);
+ tss->x86_tss.ist[IST_INDEX_DB] = CEA_ESTACK_TOP(>estacks, DB);
+ tss->x86_tss.ist[IST_INDEX_MCE] = CEA_ESTACK_TOP(>estacks, MCE);
/* Only mapped when SEV-ES is active */
- tss->x86_tss.ist[IST_INDEX_VC] = __this_cpu_ist_top_va(VC);
+ tss->x86_tss.ist[IST_INDEX_VC] = CEA_ESTACK_TOP(>estacks, VC);
}
#else /* CONFIG_X86_64 */
-static inline void setup_getcpu(int cpu) { }
-
static inline void ucode_cpu_init(int cpu)
{
show_ucode_info_early();
}
-static inline void tss_setup_ist(struct tss_struct *tss) { }
+static inline void tss_setup_ist(struct tss_struct *tss, struct cpu_entry_area
*cea) { }
#endif /* !CONFIG_X86_64 */
@@ -1854,6 +1853,17 @@ static inline void tss_setup_io_bitmap(struct tss_struct
*tss)
#endif
}
+void tss_setup(int cpu)
+{
+ struct tss_struct *tss = per_cpu_ptr(_tss_rw, cpu);
+ struct cpu_entry_area *cea = get_cpu_entry_area(cpu);
+
+ /* Initialize the TSS for cpu. */
+ tss_setup_ist(tss, cea);
+ tss_setup_io_bitmap(tss);
+ set_tss_desc(cpu, >tss.x86_tss);
+}
+
/*
* cpu_init() initializes state that is per-CPU. Some data is already
* initialized (naturally) in the bootstrap process, such as the GDT
@@ -1862,7 +1872,6 @@ static inline void tss_setup_io_bitmap(struct tss_struct
*tss)
*/
void cpu_init(void)
{
- struct tss_struct *tss = this_cpu_ptr(_tss_rw);
struct task_struct *cur = current;
int cpu = raw_smp_processor_id();
@@ -1908,10 +1917,8 @@ void cpu_init(void)
initialize_tlbstate_and_flush();
enter_lazy_tlb(_mm, cur);
- /* Initialize the TSS. */
- tss_setup_ist(tss);
- tss_setup_io_bitmap(tss);
- set_tss_desc(cpu, _cpu_entry_area(cpu)->tss.x86_tss);
+ /* Initialize the TSS - Only needed on the boot-CPU */
+ tss_setup(cpu);
load_TR_desc();
/*
diff --git a/arch/x86/kernel/head64.c
[PATCH v6 55/76] x86/sev-es: Handle DR7 read/write events
From: Tom Lendacky
Add code to handle #VC exceptions on DR7 register reads and writes.
This is needed early because show_regs() reads DR7 to print it out.
Under SEV-ES there is currently no support for saving/restoring the
DRx registers, but software expects to be able to write to the DR7
register. For now, cache the value written to DR7 and return it on
read attempts, but do not touch the real hardware DR7.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: - Adapt to #VC handling framework
- Support early usage ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-55-j...@8bytes.org
---
arch/x86/kernel/sev-es.c | 85
1 file changed, 85 insertions(+)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 379f9ad63ce8..1a7bfcb37602 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -28,6 +28,8 @@
#include
#include
+#define DR7_RESET_VALUE0x400
+
/* For early boot hypervisor communication in SEV-ES enabled guests */
static struct ghcb boot_ghcb_page __bss_decrypted __aligned(PAGE_SIZE);
@@ -75,6 +77,13 @@ struct sev_es_runtime_data {
*/
bool ghcb_active;
bool backup_ghcb_active;
+
+ /*
+* Cached DR7 value - write it on DR7 writes and return it on reads.
+* That value will never make it to the real hardware DR7 as debugging
+* is currently unsupported in SEV-ES guests.
+*/
+ unsigned long dr7;
};
struct ghcb_state {
@@ -521,6 +530,21 @@ static long *vc_insn_get_reg(struct es_em_ctxt *ctxt)
return reg_array + offset;
}
+static long *vc_insn_get_rm(struct es_em_ctxt *ctxt)
+{
+ long *reg_array;
+ int offset;
+
+ reg_array = (long *)ctxt->regs;
+ offset= insn_get_modrm_rm_off(>insn, ctxt->regs);
+
+ if (offset < 0)
+ return NULL;
+
+ offset /= sizeof(long);
+
+ return reg_array + offset;
+}
static enum es_result vc_do_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt,
unsigned int bytes, bool read)
{
@@ -768,6 +792,61 @@ static enum es_result vc_handle_mmio(struct ghcb *ghcb,
return ret;
}
+static enum es_result vc_handle_dr7_write(struct ghcb *ghcb,
+ struct es_em_ctxt *ctxt)
+{
+ struct sev_es_runtime_data *data = this_cpu_read(runtime_data);
+ long val, *reg = vc_insn_get_rm(ctxt);
+ enum es_result ret;
+
+ if (!reg)
+ return ES_DECODE_FAILED;
+
+ val = *reg;
+
+ /* Upper 32 bits must be written as zeroes */
+ if (val >> 32) {
+ ctxt->fi.vector = X86_TRAP_GP;
+ ctxt->fi.error_code = 0;
+ return ES_EXCEPTION;
+ }
+
+ /* Clear out other reserved bits and set bit 10 */
+ val = (val & 0x23ffL) | BIT(10);
+
+ /* Early non-zero writes to DR7 are not supported */
+ if (!data && (val & ~DR7_RESET_VALUE))
+ return ES_UNSUPPORTED;
+
+ /* Using a value of 0 for ExitInfo1 means RAX holds the value */
+ ghcb_set_rax(ghcb, val);
+ ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_WRITE_DR7, 0, 0);
+ if (ret != ES_OK)
+ return ret;
+
+ if (data)
+ data->dr7 = val;
+
+ return ES_OK;
+}
+
+static enum es_result vc_handle_dr7_read(struct ghcb *ghcb,
+struct es_em_ctxt *ctxt)
+{
+ struct sev_es_runtime_data *data = this_cpu_read(runtime_data);
+ long *reg = vc_insn_get_rm(ctxt);
+
+ if (!reg)
+ return ES_DECODE_FAILED;
+
+ if (data)
+ *reg = data->dr7;
+ else
+ *reg = DR7_RESET_VALUE;
+
+ return ES_OK;
+}
+
static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
struct ghcb *ghcb,
unsigned long exit_code)
@@ -775,6 +854,12 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt
*ctxt,
enum es_result result;
switch (exit_code) {
+ case SVM_EXIT_READ_DR7:
+ result = vc_handle_dr7_read(ghcb, ctxt);
+ break;
+ case SVM_EXIT_WRITE_DR7:
+ result = vc_handle_dr7_write(ghcb, ctxt);
+ break;
case SVM_EXIT_CPUID:
result = vc_handle_cpuid(ghcb, ctxt);
break;
--
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[PATCH v6 76/76] x86/sev-es: Check required CPU features for SEV-ES
From: Martin Radev
Make sure the machine supports RDRAND, otherwise there is no trusted
source of of randomness in the system.
To also check this in the pre-decompression stage, make has_cpuflag
not depend on CONFIG_RANDOMIZE_BASE anymore.
Signed-off-by: Martin Radev
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-76-j...@8bytes.org
---
arch/x86/boot/compressed/cpuflags.c | 4
arch/x86/boot/compressed/misc.h | 5 +++--
arch/x86/boot/compressed/sev-es.c | 3 +++
arch/x86/kernel/sev-es-shared.c | 15 +++
arch/x86/kernel/sev-es.c| 3 +++
5 files changed, 24 insertions(+), 6 deletions(-)
diff --git a/arch/x86/boot/compressed/cpuflags.c
b/arch/x86/boot/compressed/cpuflags.c
index 6448a8196d32..0cc1323896d1 100644
--- a/arch/x86/boot/compressed/cpuflags.c
+++ b/arch/x86/boot/compressed/cpuflags.c
@@ -1,6 +1,4 @@
// SPDX-License-Identifier: GPL-2.0
-#ifdef CONFIG_RANDOMIZE_BASE
-
#include "../cpuflags.c"
bool has_cpuflag(int flag)
@@ -9,5 +7,3 @@ bool has_cpuflag(int flag)
return test_bit(flag, cpu.flags);
}
-
-#endif
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index c0e0ffeee50a..6d31f1b4c4d1 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -85,8 +85,6 @@ void choose_random_location(unsigned long input,
unsigned long *output,
unsigned long output_size,
unsigned long *virt_addr);
-/* cpuflags.c */
-bool has_cpuflag(int flag);
#else
static inline void choose_random_location(unsigned long input,
unsigned long input_size,
@@ -97,6 +95,9 @@ static inline void choose_random_location(unsigned long input,
}
#endif
+/* cpuflags.c */
+bool has_cpuflag(int flag);
+
#ifdef CONFIG_X86_64
extern int set_page_decrypted(unsigned long address);
extern int set_page_encrypted(unsigned long address);
diff --git a/arch/x86/boot/compressed/sev-es.c
b/arch/x86/boot/compressed/sev-es.c
index b522c18c0588..eb1a8b5cc753 100644
--- a/arch/x86/boot/compressed/sev-es.c
+++ b/arch/x86/boot/compressed/sev-es.c
@@ -145,6 +145,9 @@ void sev_es_shutdown_ghcb(void)
if (!boot_ghcb)
return;
+ if (!sev_es_check_cpu_features())
+ error("SEV-ES CPU Features missing.");
+
/*
* GHCB Page must be flushed from the cache and mapped encrypted again.
* Otherwise the running kernel will see strange cache effects when
diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c
index 92d77b725ccb..ce86d2c9ca7b 100644
--- a/arch/x86/kernel/sev-es-shared.c
+++ b/arch/x86/kernel/sev-es-shared.c
@@ -9,6 +9,21 @@
* and is included directly into both code-bases.
*/
+#ifndef __BOOT_COMPRESSED
+#define error(v) pr_err(v)
+#define has_cpuflag(f) boot_cpu_has(f)
+#endif
+
+static bool __init sev_es_check_cpu_features(void)
+{
+ if (!has_cpuflag(X86_FEATURE_RDRAND)) {
+ error("RDRAND instruction not supported - no trusted source of
randomness available\n");
+ return false;
+ }
+
+ return true;
+}
+
static void sev_es_terminate(unsigned int reason)
{
u64 val = GHCB_SEV_TERMINATE;
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 2d73f5abe04b..6eadd678d1c6 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -670,6 +670,9 @@ void __init sev_es_init_vc_handling(void)
if (!sev_es_active())
return;
+ if (!sev_es_check_cpu_features())
+ panic("SEV-ES CPU Features missing");
+
/* Enable SEV-ES special handling */
static_branch_enable(_es_enable_key);
--
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[PATCH v6 38/76] x86/head/64: Set CR4.FSGSBASE early
From: Joerg Roedel Early exception handling will use rd/wrgsbase in paranoid_entry/exit. Enable the feature to avoid #UD exceptions on boot APs. Signed-off-by: Joerg Roedel Link: https://lore.kernel.org/r/20200724160336.5435-38-j...@8bytes.org --- arch/x86/kernel/head_64.S | 7 +++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 08412f308de3..4622940134a5 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -153,6 +153,13 @@ SYM_CODE_START(secondary_startup_64) orl $X86_CR4_LA57, %ecx 1: #endif + + ALTERNATIVE "jmp .Lstartup_write_cr4", "", X86_FEATURE_FSGSBASE + + /* Early exception handling uses FSGSBASE on APs */ + orl $X86_CR4_FSGSBASE, %ecx + +.Lstartup_write_cr4: movq%rcx, %cr4 /* Setup early boot stage 4-/5-level pagetables. */ -- 2.28.0 ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
[PATCH v6 13/76] x86/boot/compressed/64: Add IDT Infrastructure
From: Joerg Roedel
Add code needed to setup an IDT in the early pre-decompression
boot-code. The IDT is loaded first in startup_64, which is after
EfiExitBootServices() has been called, and later reloaded when the
kernel image has been relocated to the end of the decompression area.
This allows to setup different IDT handlers before and after the
relocation.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-13-j...@8bytes.org
---
arch/x86/boot/compressed/Makefile | 1 +
arch/x86/boot/compressed/head_64.S | 25 +++-
arch/x86/boot/compressed/idt_64.c | 44 ++
arch/x86/boot/compressed/idt_handlers_64.S | 70 ++
arch/x86/boot/compressed/misc.h| 5 ++
arch/x86/include/asm/desc_defs.h | 3 +
6 files changed, 147 insertions(+), 1 deletion(-)
create mode 100644 arch/x86/boot/compressed/idt_64.c
create mode 100644 arch/x86/boot/compressed/idt_handlers_64.S
diff --git a/arch/x86/boot/compressed/Makefile
b/arch/x86/boot/compressed/Makefile
index 0acdaa8a7dab..ce85b24898b8 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -78,6 +78,7 @@ vmlinux-objs-$(CONFIG_EARLY_PRINTK) +=
$(obj)/early_serial_console.o
vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o
ifdef CONFIG_X86_64
vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr_64.o
+ vmlinux-objs-y += $(obj)/idt_64.o $(obj)/idt_handlers_64.o
vmlinux-objs-y += $(obj)/mem_encrypt.o
vmlinux-objs-y += $(obj)/pgtable_64.o
endif
diff --git a/arch/x86/boot/compressed/head_64.S
b/arch/x86/boot/compressed/head_64.S
index 9e46729cf162..260c7940f960 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -33,6 +33,7 @@
#include
#include
#include
+#include
#include "pgtable.h"
/*
@@ -415,6 +416,10 @@ SYM_CODE_START(startup_64)
.Lon_kernel_cs:
+ pushq %rsi
+ callload_stage1_idt
+ popq%rsi
+
/*
* paging_prepare() sets up the trampoline and checks if we need to
* enable 5-level paging.
@@ -527,6 +532,13 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated)
shrq$3, %rcx
rep stosq
+/*
+ * Load stage2 IDT
+ */
+ pushq %rsi
+ callload_stage2_idt
+ popq%rsi
+
/*
* Do the extraction, and jump to the new kernel..
*/
@@ -659,10 +671,21 @@ SYM_DATA_START_LOCAL(gdt)
.quad 0x /* TS continued */
SYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end)
+SYM_DATA_START(boot_idt_desc)
+ .word boot_idt_end - boot_idt
+ .quad 0
+SYM_DATA_END(boot_idt_desc)
+ .balign 8
+SYM_DATA_START(boot_idt)
+ .rept BOOT_IDT_ENTRIES
+ .quad 0
+ .quad 0
+ .endr
+SYM_DATA_END_LABEL(boot_idt, SYM_L_GLOBAL, boot_idt_end)
+
#ifdef CONFIG_EFI_STUB
SYM_DATA(image_offset, .long 0)
#endif
-
#ifdef CONFIG_EFI_MIXED
SYM_DATA_LOCAL(efi32_boot_args, .long 0, 0, 0)
SYM_DATA(efi_is64, .byte 1)
diff --git a/arch/x86/boot/compressed/idt_64.c
b/arch/x86/boot/compressed/idt_64.c
new file mode 100644
index ..082cd6bca033
--- /dev/null
+++ b/arch/x86/boot/compressed/idt_64.c
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include
+#include
+#include
+#include "misc.h"
+
+static void set_idt_entry(int vector, void (*handler)(void))
+{
+ unsigned long address = (unsigned long)handler;
+ gate_desc entry;
+
+ memset(, 0, sizeof(entry));
+
+ entry.offset_low= (u16)(address & 0x);
+ entry.segment = __KERNEL_CS;
+ entry.bits.type = GATE_TRAP;
+ entry.bits.p= 1;
+ entry.offset_middle = (u16)((address >> 16) & 0x);
+ entry.offset_high = (u32)(address >> 32);
+
+ memcpy(_idt[vector], , sizeof(entry));
+}
+
+/* Have this here so we don't need to include */
+static void load_boot_idt(const struct desc_ptr *dtr)
+{
+ asm volatile("lidt %0"::"m" (*dtr));
+}
+
+/* Setup IDT before kernel jumping to .Lrelocated */
+void load_stage1_idt(void)
+{
+ boot_idt_desc.address = (unsigned long)boot_idt;
+
+ load_boot_idt(_idt_desc);
+}
+
+/* Setup IDT after kernel jumping to .Lrelocated */
+void load_stage2_idt(void)
+{
+ boot_idt_desc.address = (unsigned long)boot_idt;
+
+ load_boot_idt(_idt_desc);
+}
diff --git a/arch/x86/boot/compressed/idt_handlers_64.S
b/arch/x86/boot/compressed/idt_handlers_64.S
new file mode 100644
index ..36dee2f40a8b
--- /dev/null
+++ b/arch/x86/boot/compressed/idt_handlers_64.S
@@ -0,0 +1,70 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Early IDT handler entry points
+ *
+ * Copyright (C) 2019 SUSE
+ *
+ * Author: Joerg Roedel
+ */
+
+#include
+
+/* For ORIG_RAX */
+#include "../../entry/calling.h"
+
+.macro EXCEPTION_HANDLER name function error_code=0
+SYM_FUNC_START(\name)
+
+ /* Build pt_regs */
+ .if
[PATCH v6 22/76] x86/boot/compressed/64: Add set_page_en/decrypted() helpers
From: Joerg Roedel
The functions are needed to map the GHCB for SEV-ES guests. The GHCB is
used for communication with the hypervisor, so its content must not be
encrypted. After the GHCB is not needed anymore it must be mapped
encrypted again so that the running kernel image can safely re-use the
memory.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-22-j...@8bytes.org
---
arch/x86/boot/compressed/ident_map_64.c | 133
arch/x86/boot/compressed/misc.h | 2 +
2 files changed, 135 insertions(+)
diff --git a/arch/x86/boot/compressed/ident_map_64.c
b/arch/x86/boot/compressed/ident_map_64.c
index aa91bebc0fe9..05742f641a06 100644
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -24,6 +24,7 @@
/* These actually do the work of building the kernel identity maps. */
#include
+#include
#include
#include
#include
@@ -165,6 +166,138 @@ void finalize_identity_maps(void)
write_cr3(top_level_pgt);
}
+static pte_t *split_large_pmd(struct x86_mapping_info *info,
+ pmd_t *pmdp, unsigned long __address)
+{
+ unsigned long page_flags;
+ unsigned long address;
+ pte_t *pte;
+ pmd_t pmd;
+ int i;
+
+ pte = (pte_t *)info->alloc_pgt_page(info->context);
+ if (!pte)
+ return NULL;
+
+ address = __address & PMD_MASK;
+ /* No large page - clear PSE flag */
+ page_flags = info->page_flag & ~_PAGE_PSE;
+
+ /* Populate the PTEs */
+ for (i = 0; i < PTRS_PER_PMD; i++) {
+ set_pte([i], __pte(address | page_flags));
+ address += PAGE_SIZE;
+ }
+
+ /*
+* Ideally we need to clear the large PMD first and do a TLB
+* flush before we write the new PMD. But the 2M range of the
+* PMD might contain the code we execute and/or the stack
+* we are on, so we can't do that. But that should be safe here
+* because we are going from large to small mappings and we are
+* also the only user of the page-table, so there is no chance
+* of a TLB multihit.
+*/
+ pmd = __pmd((unsigned long)pte | info->kernpg_flag);
+ set_pmd(pmdp, pmd);
+ /* Flush TLB to establish the new PMD */
+ write_cr3(top_level_pgt);
+
+ return pte + pte_index(__address);
+}
+
+static void clflush_page(unsigned long address)
+{
+ unsigned int flush_size;
+ char *cl, *start, *end;
+
+ /*
+* Hardcode cl-size to 64 - CPUID can't be used here because that might
+* cause another #VC exception and the GHCB is not ready to use yet.
+*/
+ flush_size = 64;
+ start = (char *)(address & PAGE_MASK);
+ end= start + PAGE_SIZE;
+
+ /*
+* First make sure there are no pending writes on the cache-lines to
+* flush.
+*/
+ asm volatile("mfence" : : : "memory");
+
+ for (cl = start; cl != end; cl += flush_size)
+ clflush(cl);
+}
+
+static int set_clr_page_flags(struct x86_mapping_info *info,
+ unsigned long address,
+ pteval_t set, pteval_t clr)
+{
+ pgd_t *pgdp = (pgd_t *)top_level_pgt;
+ p4d_t *p4dp;
+ pud_t *pudp;
+ pmd_t *pmdp;
+ pte_t *ptep, pte;
+
+ /*
+* First make sure there is a PMD mapping for 'address'.
+* It should already exist, but keep things generic.
+*
+* To map the page just read from it and fault it in if there is no
+* mapping yet. add_identity_map() can't be called here because that
+* would unconditionally map the address on PMD level, destroying any
+* PTE-level mappings that might already exist. Use assembly here so
+* the access won't be optimized away.
+*/
+ asm volatile("mov %[address], %%r9"
+:: [address] "g" (*(unsigned long *)address)
+: "r9", "memory");
+
+ /*
+* The page is mapped at least with PMD size - so skip checks and walk
+* directly to the PMD.
+*/
+ p4dp = p4d_offset(pgdp, address);
+ pudp = pud_offset(p4dp, address);
+ pmdp = pmd_offset(pudp, address);
+
+ if (pmd_large(*pmdp))
+ ptep = split_large_pmd(info, pmdp, address);
+ else
+ ptep = pte_offset_kernel(pmdp, address);
+
+ if (!ptep)
+ return -ENOMEM;
+
+ /*
+* Changing encryption attributes of a page requires to flush it from
+* the caches.
+*/
+ if ((set | clr) & _PAGE_ENC)
+ clflush_page(address);
+
+ /* Update PTE */
+ pte = *ptep;
+ pte = pte_set_flags(pte, set);
+ pte = pte_clear_flags(pte, clr);
+ set_pte(ptep, pte);
+
+ /* Flush TLB after changing encryption attribute */
+
[PATCH v6 14/76] x86/boot/compressed/64: Rename kaslr_64.c to ident_map_64.c
From: Joerg Roedel
The file contains only code related to identity mapped page-tables.
Rename the file and compile it always in.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-14-j...@8bytes.org
---
arch/x86/boot/compressed/Makefile | 2 +-
arch/x86/boot/compressed/{kaslr_64.c => ident_map_64.c} | 9 +
arch/x86/boot/compressed/kaslr.c| 9 -
arch/x86/boot/compressed/misc.h | 8
4 files changed, 18 insertions(+), 10 deletions(-)
rename arch/x86/boot/compressed/{kaslr_64.c => ident_map_64.c} (95%)
diff --git a/arch/x86/boot/compressed/Makefile
b/arch/x86/boot/compressed/Makefile
index ce85b24898b8..822e61a0d51b 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -77,7 +77,7 @@ vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/kernel_info.o
$(obj)/head_$(BITS).o
vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o
vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o
ifdef CONFIG_X86_64
- vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr_64.o
+ vmlinux-objs-y += $(obj)/ident_map_64.o
vmlinux-objs-y += $(obj)/idt_64.o $(obj)/idt_handlers_64.o
vmlinux-objs-y += $(obj)/mem_encrypt.o
vmlinux-objs-y += $(obj)/pgtable_64.o
diff --git a/arch/x86/boot/compressed/kaslr_64.c
b/arch/x86/boot/compressed/ident_map_64.c
similarity index 95%
rename from arch/x86/boot/compressed/kaslr_64.c
rename to arch/x86/boot/compressed/ident_map_64.c
index f9c5c13d979b..d9932a133ac9 100644
--- a/arch/x86/boot/compressed/kaslr_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -29,6 +29,15 @@
#define __PAGE_OFFSET __PAGE_OFFSET_BASE
#include "../../mm/ident_map.c"
+#ifdef CONFIG_X86_5LEVEL
+unsigned int __pgtable_l5_enabled;
+unsigned int pgdir_shift = 39;
+unsigned int ptrs_per_p4d = 1;
+#endif
+
+/* Used by PAGE_KERN* macros: */
+pteval_t __default_kernel_pte_mask __read_mostly = ~0;
+
/* Used to track our page table allocation area. */
struct alloc_pgt_data {
unsigned char *pgt_buf;
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 0e9fbc90ddc4..0b1551f19920 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -40,17 +40,8 @@
#include /* For COMMAND_LINE_SIZE */
#undef _SETUP
-#ifdef CONFIG_X86_5LEVEL
-unsigned int __pgtable_l5_enabled;
-unsigned int pgdir_shift __ro_after_init = 39;
-unsigned int ptrs_per_p4d __ro_after_init = 1;
-#endif
-
extern unsigned long get_cmd_line_ptr(void);
-/* Used by PAGE_KERN* macros: */
-pteval_t __default_kernel_pte_mask __read_mostly = ~0;
-
/* Simplified build-specific string for starting entropy. */
static const char build_str[] = UTS_RELEASE " (" LINUX_COMPILE_BY "@"
LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION;
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 8feb5f6f329e..98b7a1df9c59 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -134,6 +134,14 @@ int count_immovable_mem_regions(void);
static inline int count_immovable_mem_regions(void) { return 0; }
#endif
+/* ident_map_64.c */
+#ifdef CONFIG_X86_5LEVEL
+extern unsigned int __pgtable_l5_enabled, pgdir_shift, ptrs_per_p4d;
+#endif
+
+/* Used by PAGE_KERN* macros: */
+extern pteval_t __default_kernel_pte_mask;
+
/* idt_64.c */
extern gate_desc boot_idt[BOOT_IDT_ENTRIES];
extern struct desc_ptr boot_idt_desc;
--
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[PATCH v6 03/76] KVM: SVM: Add GHCB Accessor functions
From: Joerg Roedel
Building a correct GHCB for the hypervisor requires setting valid bits
in the GHCB. Simplify that process by providing accessor functions to
set values and to update the valid bitmap and to check the valid bitmap
in KVM.
Signed-off-by: Joerg Roedel
---
arch/x86/include/asm/svm.h | 43 ++
1 file changed, 43 insertions(+)
diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 094b8f8fb1d4..50e5fa8d3249 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -341,4 +341,47 @@ struct __attribute__ ((__packed__)) vmcb {
#define SVM_CR0_SELECTIVE_MASK (X86_CR0_TS | X86_CR0_MP)
+/* GHCB Accessor functions */
+
+#define GHCB_BITMAP_IDX(field)
\
+ (offsetof(struct vmcb_save_area, field) / sizeof(u64))
+
+#define DEFINE_GHCB_ACCESSORS(field)
\
+ static inline bool ghcb_##field##_is_valid(const struct ghcb *ghcb)
\
+ {
\
+ return test_bit(GHCB_BITMAP_IDX(field),
\
+ (unsigned long *)>save.valid_bitmap);
\
+ }
\
+
\
+ static inline void ghcb_set_##field(struct ghcb *ghcb, u64 value)
\
+ {
\
+ __set_bit(GHCB_BITMAP_IDX(field),
\
+ (unsigned long *)>save.valid_bitmap);
\
+ ghcb->save.field = value;
\
+ }
+
+DEFINE_GHCB_ACCESSORS(cpl)
+DEFINE_GHCB_ACCESSORS(rip)
+DEFINE_GHCB_ACCESSORS(rsp)
+DEFINE_GHCB_ACCESSORS(rax)
+DEFINE_GHCB_ACCESSORS(rcx)
+DEFINE_GHCB_ACCESSORS(rdx)
+DEFINE_GHCB_ACCESSORS(rbx)
+DEFINE_GHCB_ACCESSORS(rbp)
+DEFINE_GHCB_ACCESSORS(rsi)
+DEFINE_GHCB_ACCESSORS(rdi)
+DEFINE_GHCB_ACCESSORS(r8)
+DEFINE_GHCB_ACCESSORS(r9)
+DEFINE_GHCB_ACCESSORS(r10)
+DEFINE_GHCB_ACCESSORS(r11)
+DEFINE_GHCB_ACCESSORS(r12)
+DEFINE_GHCB_ACCESSORS(r13)
+DEFINE_GHCB_ACCESSORS(r14)
+DEFINE_GHCB_ACCESSORS(r15)
+DEFINE_GHCB_ACCESSORS(sw_exit_code)
+DEFINE_GHCB_ACCESSORS(sw_exit_info_1)
+DEFINE_GHCB_ACCESSORS(sw_exit_info_2)
+DEFINE_GHCB_ACCESSORS(sw_scratch)
+DEFINE_GHCB_ACCESSORS(xcr0)
+
#endif
--
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[PATCH v6 09/76] x86/umip: Factor out instruction decoding
From: Joerg Roedel
Factor out the code used to decode an instruction with the correct
address and operand sizes to a helper function.
No functional changes.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-9-j...@8bytes.org
---
arch/x86/include/asm/insn-eval.h | 2 ++
arch/x86/kernel/umip.c | 23 +---
arch/x86/lib/insn-eval.c | 45
3 files changed, 48 insertions(+), 22 deletions(-)
diff --git a/arch/x86/include/asm/insn-eval.h b/arch/x86/include/asm/insn-eval.h
index b8b9ef1bbd06..392b4fe377f9 100644
--- a/arch/x86/include/asm/insn-eval.h
+++ b/arch/x86/include/asm/insn-eval.h
@@ -21,5 +21,7 @@ unsigned long insn_get_seg_base(struct pt_regs *regs, int
seg_reg_idx);
int insn_get_code_seg_params(struct pt_regs *regs);
int insn_fetch_from_user(struct pt_regs *regs,
unsigned char buf[MAX_INSN_SIZE]);
+bool insn_decode(struct insn *insn, struct pt_regs *regs,
+unsigned char buf[MAX_INSN_SIZE], int buf_size);
#endif /* _ASM_X86_INSN_EVAL_H */
diff --git a/arch/x86/kernel/umip.c b/arch/x86/kernel/umip.c
index ad135be4f1f0..f6225bf22c02 100644
--- a/arch/x86/kernel/umip.c
+++ b/arch/x86/kernel/umip.c
@@ -342,7 +342,6 @@ bool fixup_umip_exception(struct pt_regs *regs)
unsigned long *reg_addr;
void __user *uaddr;
struct insn insn;
- int seg_defs;
if (!regs)
return false;
@@ -357,27 +356,7 @@ bool fixup_umip_exception(struct pt_regs *regs)
if (!nr_copied)
return false;
- insn_init(, buf, nr_copied, user_64bit_mode(regs));
-
- /*
-* Override the default operand and address sizes with what is specified
-* in the code segment descriptor. The instruction decoder only sets
-* the address size it to either 4 or 8 address bytes and does nothing
-* for the operand bytes. This OK for most of the cases, but we could
-* have special cases where, for instance, a 16-bit code segment
-* descriptor is used.
-* If there is an address override prefix, the instruction decoder
-* correctly updates these values, even for 16-bit defaults.
-*/
- seg_defs = insn_get_code_seg_params(regs);
- if (seg_defs == -EINVAL)
- return false;
-
- insn.addr_bytes = INSN_CODE_SEG_ADDR_SZ(seg_defs);
- insn.opnd_bytes = INSN_CODE_SEG_OPND_SZ(seg_defs);
-
- insn_get_length();
- if (nr_copied < insn.length)
+ if (!insn_decode(, regs, buf, nr_copied))
return false;
umip_inst = identify_insn();
diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c
index 0c4f7ebc261b..f52046f90dd3 100644
--- a/arch/x86/lib/insn-eval.c
+++ b/arch/x86/lib/insn-eval.c
@@ -1407,3 +1407,48 @@ int insn_fetch_from_user(struct pt_regs *regs, unsigned
char buf[MAX_INSN_SIZE])
return MAX_INSN_SIZE - not_copied;
}
+
+/**
+ * insn_decode() - Decode an instruction
+ * @insn: Structure to store decoded instruction
+ * @regs: Structure with register values as seen when entering kernel mode
+ * @buf: Buffer containing the instruction bytes
+ * @buf_size: Number of instruction bytes available in buf
+ *
+ * Decodes the instruction provided in buf and stores the decoding results in
+ * insn. Also determines the correct address and operand sizes.
+ *
+ * Returns:
+ *
+ * True if instruction was decoded, False otherwise.
+ */
+bool insn_decode(struct insn *insn, struct pt_regs *regs,
+unsigned char buf[MAX_INSN_SIZE], int buf_size)
+{
+ int seg_defs;
+
+ insn_init(insn, buf, buf_size, user_64bit_mode(regs));
+
+ /*
+* Override the default operand and address sizes with what is specified
+* in the code segment descriptor. The instruction decoder only sets
+* the address size it to either 4 or 8 address bytes and does nothing
+* for the operand bytes. This OK for most of the cases, but we could
+* have special cases where, for instance, a 16-bit code segment
+* descriptor is used.
+* If there is an address override prefix, the instruction decoder
+* correctly updates these values, even for 16-bit defaults.
+*/
+ seg_defs = insn_get_code_seg_params(regs);
+ if (seg_defs == -EINVAL)
+ return false;
+
+ insn->addr_bytes = INSN_CODE_SEG_ADDR_SZ(seg_defs);
+ insn->opnd_bytes = INSN_CODE_SEG_OPND_SZ(seg_defs);
+
+ insn_get_length(insn);
+ if (buf_size < insn->length)
+ return false;
+
+ return true;
+}
--
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[PATCH v6 33/76] x86/head/64: Load segment registers earlier
From: Joerg Roedel Make sure segments are properly set up before setting up an IDT and doing anything that might cause a #VC exception. This is later needed for early exception handling. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20200724160336.5435-33-j...@8bytes.org --- arch/x86/kernel/head_64.S | 52 +++ 1 file changed, 26 insertions(+), 26 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index f958d4e4ee08..057c7bd3eeb6 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -174,6 +174,32 @@ SYM_CODE_START(secondary_startup_64) */ lgdtearly_gdt_descr(%rip) + /* set up data segments */ + xorl %eax,%eax + movl %eax,%ds + movl %eax,%ss + movl %eax,%es + + /* +* We don't really need to load %fs or %gs, but load them anyway +* to kill any stale realmode selectors. This allows execution +* under VT hardware. +*/ + movl %eax,%fs + movl %eax,%gs + + /* Set up %gs. +* +* The base of %gs always points to fixed_percpu_data. If the +* stack protector canary is enabled, it is located at %gs:40. +* Note that, on SMP, the boot cpu uses init data section until +* the per cpu areas are set up. +*/ + movl$MSR_GS_BASE,%ecx + movlinitial_gs(%rip),%eax + movlinitial_gs+4(%rip),%edx + wrmsr + /* Check if nx is implemented */ movl$0x8001, %eax cpuid @@ -201,32 +227,6 @@ SYM_CODE_START(secondary_startup_64) pushq $0 popfq - /* set up data segments */ - xorl %eax,%eax - movl %eax,%ds - movl %eax,%ss - movl %eax,%es - - /* -* We don't really need to load %fs or %gs, but load them anyway -* to kill any stale realmode selectors. This allows execution -* under VT hardware. -*/ - movl %eax,%fs - movl %eax,%gs - - /* Set up %gs. -* -* The base of %gs always points to fixed_percpu_data. If the -* stack protector canary is enabled, it is located at %gs:40. -* Note that, on SMP, the boot cpu uses init data section until -* the per cpu areas are set up. -*/ - movl$MSR_GS_BASE,%ecx - movlinitial_gs(%rip),%eax - movlinitial_gs+4(%rip),%edx - wrmsr - /* rsi is pointer to real mode structure with interesting info. pass it to C */ movq%rsi, %rdi -- 2.28.0 ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
[PATCH v6 31/76] x86/head/64: Setup MSR_GS_BASE before calling into C code
From: Joerg Roedel
When stack-protector is enabled a valid GS_BASE is needed before
calling any C code function, because the stack canary is loaded from
per-cpu data.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-31-j...@8bytes.org
---
arch/x86/kernel/head64.c | 7 +++
arch/x86/kernel/head_64.S | 8
2 files changed, 15 insertions(+)
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 8c82be44be94..b0ab5627900b 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -36,6 +36,7 @@
#include
#include
#include
+#include
/*
* Manage page tables very early on.
@@ -513,6 +514,8 @@ void __init x86_64_start_reservations(char *real_mode_data)
*/
void __head startup_64_setup_env(unsigned long physbase)
{
+ unsigned long gsbase;
+
/* Load GDT */
startup_gdt_descr.address = (unsigned long)fixup_pointer(startup_gdt,
physbase);
native_load_gdt(_gdt_descr);
@@ -521,4 +524,8 @@ void __head startup_64_setup_env(unsigned long physbase)
asm volatile("movl %%eax, %%ds\n"
"movl %%eax, %%ss\n"
"movl %%eax, %%es\n" : : "a"(__KERNEL_DS) : "memory");
+
+ /* Setup GS_BASE - needed for stack protector */
+ gsbase = (unsigned long)fixup_pointer((void *)initial_gs, physbase);
+ __wrmsr(MSR_GS_BASE, (u32)gsbase, (u32)(gsbase >> 32));
}
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 2b2e91627221..800053219054 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -78,6 +78,14 @@ SYM_CODE_START_NOALIGN(startup_64)
callstartup_64_setup_env
popq%rsi
+ /*
+* Setup %gs here already to make stack-protector work - it needs to be
+* setup again after the switch to kernel addresses. The address read
+* from initial_gs is a kernel address, so it needs to be adjusted first
+* for the identity mapping.
+*/
+ movl$MSR_GS_BASE,%ecx
+
/* Now switch to __KERNEL_CS so IRET works reliably */
pushq $__KERNEL_CS
leaq.Lon_kernel_cs(%rip), %rax
--
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[PATCH v6 16/76] x86/boot/compressed/64: Always switch to own page-table
From: Joerg Roedel
When booted through startup_64 the kernel keeps running on the EFI
page-table until the KASLR code sets up its own page-table. Without
KASLR the pre-decompression boot code never switches off the EFI
page-table. Change that by unconditionally switching to a kernel
controlled page-table after relocation.
This makes sure we can make changes to the mapping when necessary, for
example map pages unencrypted in SEV and SEV-ES guests.
Also remove the debug_putstr() calls in initialize_identity_maps()
because the function now runs before console_init() is called.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-16-j...@8bytes.org
---
arch/x86/boot/compressed/head_64.S | 3 +-
arch/x86/boot/compressed/ident_map_64.c | 51 +++--
arch/x86/boot/compressed/kaslr.c| 3 --
3 files changed, 32 insertions(+), 25 deletions(-)
diff --git a/arch/x86/boot/compressed/head_64.S
b/arch/x86/boot/compressed/head_64.S
index 260c7940f960..013b29921836 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -533,10 +533,11 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated)
rep stosq
/*
- * Load stage2 IDT
+ * Load stage2 IDT and switch to our own page-table
*/
pushq %rsi
callload_stage2_idt
+ callinitialize_identity_maps
popq%rsi
/*
diff --git a/arch/x86/boot/compressed/ident_map_64.c
b/arch/x86/boot/compressed/ident_map_64.c
index e3d980ae9c2b..ecf9353b064d 100644
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -86,9 +86,31 @@ phys_addr_t physical_mask = (1ULL << __PHYSICAL_MASK_SHIFT)
- 1;
*/
static struct x86_mapping_info mapping_info;
+/*
+ * Adds the specified range to what will become the new identity mappings.
+ * Once all ranges have been added, the new mapping is activated by calling
+ * finalize_identity_maps() below.
+ */
+void add_identity_map(unsigned long start, unsigned long size)
+{
+ unsigned long end = start + size;
+
+ /* Align boundary to 2M. */
+ start = round_down(start, PMD_SIZE);
+ end = round_up(end, PMD_SIZE);
+ if (start >= end)
+ return;
+
+ /* Build the mapping. */
+ kernel_ident_mapping_init(_info, (pgd_t *)top_level_pgt,
+ start, end);
+}
+
/* Locates and clears a region for a new top level page table. */
void initialize_identity_maps(void)
{
+ unsigned long start, size;
+
/* If running as an SEV guest, the encryption mask is required. */
set_sev_encryption_mask();
@@ -121,37 +143,24 @@ void initialize_identity_maps(void)
*/
top_level_pgt = read_cr3_pa();
if (p4d_offset((pgd_t *)top_level_pgt, 0) == (p4d_t *)_pgtable) {
- debug_putstr("booted via startup_32()\n");
pgt_data.pgt_buf = _pgtable + BOOT_INIT_PGT_SIZE;
pgt_data.pgt_buf_size = BOOT_PGT_SIZE - BOOT_INIT_PGT_SIZE;
memset(pgt_data.pgt_buf, 0, pgt_data.pgt_buf_size);
} else {
- debug_putstr("booted via startup_64()\n");
pgt_data.pgt_buf = _pgtable;
pgt_data.pgt_buf_size = BOOT_PGT_SIZE;
memset(pgt_data.pgt_buf, 0, pgt_data.pgt_buf_size);
top_level_pgt = (unsigned long)alloc_pgt_page(_data);
}
-}
-/*
- * Adds the specified range to what will become the new identity mappings.
- * Once all ranges have been added, the new mapping is activated by calling
- * finalize_identity_maps() below.
- */
-void add_identity_map(unsigned long start, unsigned long size)
-{
- unsigned long end = start + size;
-
- /* Align boundary to 2M. */
- start = round_down(start, PMD_SIZE);
- end = round_up(end, PMD_SIZE);
- if (start >= end)
- return;
-
- /* Build the mapping. */
- kernel_ident_mapping_init(_info, (pgd_t *)top_level_pgt,
- start, end);
+ /*
+* New page-table is set up - map the kernel image and load it
+* into cr3.
+*/
+ start = (unsigned long)_head;
+ size = _end - _head;
+ add_identity_map(start, size);
+ write_cr3(top_level_pgt);
}
/*
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 0b1551f19920..9016f2268aa7 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -861,9 +861,6 @@ void choose_random_location(unsigned long input,
boot_params->hdr.loadflags |= KASLR_FLAG;
- /* Prepare to add new identity pagetables on demand. */
- initialize_identity_maps();
-
if (IS_ENABLED(CONFIG_X86_32))
mem_limit = KERNEL_IMAGE_SIZE;
else
--
2.28.0
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[PATCH v6 25/76] x86/sev-es: Add support for handling IOIO exceptions
From: Tom Lendacky
Add support for decoding and handling #VC exceptions for IOIO events.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: Adapted code to #VC handling framework ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-25-j...@8bytes.org
---
arch/x86/boot/compressed/sev-es.c | 32 +
arch/x86/kernel/sev-es-shared.c | 214 ++
2 files changed, 246 insertions(+)
diff --git a/arch/x86/boot/compressed/sev-es.c
b/arch/x86/boot/compressed/sev-es.c
index e3abf8737015..4f2fc7a85c2f 100644
--- a/arch/x86/boot/compressed/sev-es.c
+++ b/arch/x86/boot/compressed/sev-es.c
@@ -24,6 +24,35 @@
struct ghcb boot_ghcb_page __aligned(PAGE_SIZE);
struct ghcb *boot_ghcb;
+/*
+ * Copy a version of this function here - insn-eval.c can't be used in
+ * pre-decompression code.
+ */
+static bool insn_has_rep_prefix(struct insn *insn)
+{
+ int i;
+
+ insn_get_prefixes(insn);
+
+ for (i = 0; i < insn->prefixes.nbytes; i++) {
+ insn_byte_t p = insn->prefixes.bytes[i];
+
+ if (p == 0xf2 || p == 0xf3)
+ return true;
+ }
+
+ return false;
+}
+
+/*
+ * Only a dummy for insn_get_seg_base() - Early boot-code is 64bit only and
+ * doesn't use segments.
+ */
+static unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx)
+{
+ return 0UL;
+}
+
static inline u64 sev_es_rd_ghcb_msr(void)
{
unsigned long low, high;
@@ -151,6 +180,9 @@ void do_boot_stage2_vc(struct pt_regs *regs, unsigned long
exit_code)
goto finish;
switch (exit_code) {
+ case SVM_EXIT_IOIO:
+ result = vc_handle_ioio(boot_ghcb, );
+ break;
default:
result = ES_UNSUPPORTED;
break;
diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c
index 7ac6e6b0ae57..bae7cf28455b 100644
--- a/arch/x86/kernel/sev-es-shared.c
+++ b/arch/x86/kernel/sev-es-shared.c
@@ -218,3 +218,217 @@ static enum es_result vc_insn_string_write(struct
es_em_ctxt *ctxt,
return ret;
}
+
+#define IOIO_TYPE_STR BIT(2)
+#define IOIO_TYPE_IN 1
+#define IOIO_TYPE_INS (IOIO_TYPE_IN | IOIO_TYPE_STR)
+#define IOIO_TYPE_OUT 0
+#define IOIO_TYPE_OUTS (IOIO_TYPE_OUT | IOIO_TYPE_STR)
+
+#define IOIO_REP BIT(3)
+
+#define IOIO_ADDR_64 BIT(9)
+#define IOIO_ADDR_32 BIT(8)
+#define IOIO_ADDR_16 BIT(7)
+
+#define IOIO_DATA_32 BIT(6)
+#define IOIO_DATA_16 BIT(5)
+#define IOIO_DATA_8BIT(4)
+
+#define IOIO_SEG_ES(0 << 10)
+#define IOIO_SEG_DS(3 << 10)
+
+static enum es_result vc_ioio_exitinfo(struct es_em_ctxt *ctxt, u64 *exitinfo)
+{
+ struct insn *insn = >insn;
+ *exitinfo = 0;
+
+ switch (insn->opcode.bytes[0]) {
+ /* INS opcodes */
+ case 0x6c:
+ case 0x6d:
+ *exitinfo |= IOIO_TYPE_INS;
+ *exitinfo |= IOIO_SEG_ES;
+ *exitinfo |= (ctxt->regs->dx & 0x) << 16;
+ break;
+
+ /* OUTS opcodes */
+ case 0x6e:
+ case 0x6f:
+ *exitinfo |= IOIO_TYPE_OUTS;
+ *exitinfo |= IOIO_SEG_DS;
+ *exitinfo |= (ctxt->regs->dx & 0x) << 16;
+ break;
+
+ /* IN immediate opcodes */
+ case 0xe4:
+ case 0xe5:
+ *exitinfo |= IOIO_TYPE_IN;
+ *exitinfo |= (u64)insn->immediate.value << 16;
+ break;
+
+ /* OUT immediate opcodes */
+ case 0xe6:
+ case 0xe7:
+ *exitinfo |= IOIO_TYPE_OUT;
+ *exitinfo |= (u64)insn->immediate.value << 16;
+ break;
+
+ /* IN register opcodes */
+ case 0xec:
+ case 0xed:
+ *exitinfo |= IOIO_TYPE_IN;
+ *exitinfo |= (ctxt->regs->dx & 0x) << 16;
+ break;
+
+ /* OUT register opcodes */
+ case 0xee:
+ case 0xef:
+ *exitinfo |= IOIO_TYPE_OUT;
+ *exitinfo |= (ctxt->regs->dx & 0x) << 16;
+ break;
+
+ default:
+ return ES_DECODE_FAILED;
+ }
+
+ switch (insn->opcode.bytes[0]) {
+ case 0x6c:
+ case 0x6e:
+ case 0xe4:
+ case 0xe6:
+ case 0xec:
+ case 0xee:
+ /* Single byte opcodes */
+ *exitinfo |= IOIO_DATA_8;
+ break;
+ default:
+ /* Length determined by instruction parsing */
+ *exitinfo |= (insn->opnd_bytes == 2) ? IOIO_DATA_16
+: IOIO_DATA_32;
+ }
+ switch (insn->addr_bytes) {
+ case 2:
+ *exitinfo |= IOIO_ADDR_16;
+ break;
+ case 4:
+ *exitinfo |= IOIO_ADDR_32;
+ break;
+ case 8:
+ *exitinfo |= IOIO_ADDR_64;
+ break;
+ }
+
+ if
[PATCH v6 26/76] x86/fpu: Move xgetbv()/xsetbv() into separate header
From: Joerg Roedel
The xgetbv() function is needed in pre-decompression boot code, but
asm/fpu/internal.h can't be included there directly. Doing so opens
the door to include-hell due to various include-magic in
boot/compressed/misc.h.
Avoid that by moving xgetbv()/xsetbv() to a separate header file and
include this instead.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-26-j...@8bytes.org
---
arch/x86/include/asm/fpu/internal.h | 30 +
arch/x86/include/asm/fpu/xcr.h | 34 +
2 files changed, 35 insertions(+), 29 deletions(-)
create mode 100644 arch/x86/include/asm/fpu/xcr.h
diff --git a/arch/x86/include/asm/fpu/internal.h
b/arch/x86/include/asm/fpu/internal.h
index 21a8b5259477..ceeba9f63172 100644
--- a/arch/x86/include/asm/fpu/internal.h
+++ b/arch/x86/include/asm/fpu/internal.h
@@ -19,6 +19,7 @@
#include
#include
#include
+#include
#include
#include
@@ -585,33 +586,4 @@ static inline void switch_fpu_finish(struct fpu *new_fpu)
__write_pkru(pkru_val);
}
-/*
- * MXCSR and XCR definitions:
- */
-
-static inline void ldmxcsr(u32 mxcsr)
-{
- asm volatile("ldmxcsr %0" :: "m" (mxcsr));
-}
-
-extern unsigned int mxcsr_feature_mask;
-
-#define XCR_XFEATURE_ENABLED_MASK 0x
-
-static inline u64 xgetbv(u32 index)
-{
- u32 eax, edx;
-
- asm volatile("xgetbv" : "=a" (eax), "=d" (edx) : "c" (index));
- return eax + ((u64)edx << 32);
-}
-
-static inline void xsetbv(u32 index, u64 value)
-{
- u32 eax = value;
- u32 edx = value >> 32;
-
- asm volatile("xsetbv" :: "a" (eax), "d" (edx), "c" (index));
-}
-
#endif /* _ASM_X86_FPU_INTERNAL_H */
diff --git a/arch/x86/include/asm/fpu/xcr.h b/arch/x86/include/asm/fpu/xcr.h
new file mode 100644
index ..1c7ab8d95da5
--- /dev/null
+++ b/arch/x86/include/asm/fpu/xcr.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_FPU_XCR_H
+#define _ASM_X86_FPU_XCR_H
+
+/*
+ * MXCSR and XCR definitions:
+ */
+
+static inline void ldmxcsr(u32 mxcsr)
+{
+ asm volatile("ldmxcsr %0" :: "m" (mxcsr));
+}
+
+extern unsigned int mxcsr_feature_mask;
+
+#define XCR_XFEATURE_ENABLED_MASK 0x
+
+static inline u64 xgetbv(u32 index)
+{
+ u32 eax, edx;
+
+ asm volatile("xgetbv" : "=a" (eax), "=d" (edx) : "c" (index));
+ return eax + ((u64)edx << 32);
+}
+
+static inline void xsetbv(u32 index, u64 value)
+{
+ u32 eax = value;
+ u32 edx = value >> 32;
+
+ asm volatile("xsetbv" :: "a" (eax), "d" (edx), "c" (index));
+}
+
+#endif /* _ASM_X86_FPU_XCR_H */
--
2.28.0
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[PATCH v6 30/76] x86/head/64: Install startup GDT
From: Joerg Roedel
Handling exceptions during boot requires a working GDT. The kernel GDT
can't be used on the direct mapping, so load a startup GDT and setup
segments.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-30-j...@8bytes.org
---
arch/x86/include/asm/setup.h | 1 +
arch/x86/kernel/head64.c | 33 +
arch/x86/kernel/head_64.S| 14 ++
3 files changed, 48 insertions(+)
diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h
index 84b645cc8bc9..5c2fd05bd52c 100644
--- a/arch/x86/include/asm/setup.h
+++ b/arch/x86/include/asm/setup.h
@@ -48,6 +48,7 @@ extern void reserve_standard_io_resources(void);
extern void i386_reserve_resources(void);
extern unsigned long __startup_64(unsigned long physaddr, struct boot_params
*bp);
extern unsigned long __startup_secondary_64(void);
+extern void startup_64_setup_env(unsigned long physbase);
extern int early_make_pgtable(unsigned long address);
#ifdef CONFIG_X86_INTEL_MID
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index cbb71c1b574f..8c82be44be94 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -61,6 +61,24 @@ unsigned long vmemmap_base __ro_after_init =
__VMEMMAP_BASE_L4;
EXPORT_SYMBOL(vmemmap_base);
#endif
+/*
+ * GDT used on the boot CPU before switching to virtual addresses.
+ */
+static struct desc_struct startup_gdt[GDT_ENTRIES] = {
+ [GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(0xc09b, 0, 0xf),
+ [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xa09b, 0, 0xf),
+ [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc093, 0, 0xf),
+};
+
+/*
+ * Address needs to be set at runtime because it references the startup_gdt
+ * while the kernel still uses a direct mapping.
+ */
+static struct desc_ptr startup_gdt_descr = {
+ .size = sizeof(startup_gdt),
+ .address = 0,
+};
+
#define __head __section(.head.text)
static void __head *fixup_pointer(void *ptr, unsigned long physaddr)
@@ -489,3 +507,18 @@ void __init x86_64_start_reservations(char *real_mode_data)
start_kernel();
}
+
+/*
+ * Setup boot CPU state needed before kernel switches to virtual addresses.
+ */
+void __head startup_64_setup_env(unsigned long physbase)
+{
+ /* Load GDT */
+ startup_gdt_descr.address = (unsigned long)fixup_pointer(startup_gdt,
physbase);
+ native_load_gdt(_gdt_descr);
+
+ /* New GDT is live - reload data segment registers */
+ asm volatile("movl %%eax, %%ds\n"
+"movl %%eax, %%ss\n"
+"movl %%eax, %%es\n" : : "a"(__KERNEL_DS) : "memory");
+}
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 16da4ac01597..2b2e91627221 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -73,6 +73,20 @@ SYM_CODE_START_NOALIGN(startup_64)
/* Set up the stack for verify_cpu(), similar to initial_stack below */
leaq(__end_init_task - SIZEOF_PTREGS)(%rip), %rsp
+ leaq_text(%rip), %rdi
+ pushq %rsi
+ callstartup_64_setup_env
+ popq%rsi
+
+ /* Now switch to __KERNEL_CS so IRET works reliably */
+ pushq $__KERNEL_CS
+ leaq.Lon_kernel_cs(%rip), %rax
+ pushq %rax
+ lretq
+
+.Lon_kernel_cs:
+ UNWIND_HINT_EMPTY
+
/* Sanitize CPU configuration */
call verify_cpu
--
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[PATCH v6 28/76] x86/idt: Move IDT to data segment
From: Joerg Roedel
With SEV-ES, exception handling is needed very early, even before the
kernel has cleared the bss segment. In order to prevent clearing the
currently used IDT, move the IDT to the data segment.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-28-j...@8bytes.org
---
arch/x86/kernel/idt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index 7ecf9babf0cb..34fcc58b81b5 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -158,7 +158,7 @@ static const __initconst struct idt_data apic_idts[] = {
};
/* Must be page-aligned because the real IDT is used in the cpu entry area */
-static gate_desc idt_table[IDT_ENTRIES] __page_aligned_bss;
+static gate_desc idt_table[IDT_ENTRIES] __page_aligned_data;
static struct desc_ptr idt_descr __ro_after_init = {
.size = IDT_TABLE_SIZE - 1,
--
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[PATCH v6 39/76] x86/sev-es: Add SEV-ES Feature Detection
From: Joerg Roedel
Add the sev_es_active function for checking whether SEV-ES is enabled.
Also cache the value of MSR_AMD64_SEV at boot to speed up the feature
checking in the running code.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-39-j...@8bytes.org
---
arch/x86/include/asm/mem_encrypt.h | 3 +++
arch/x86/include/asm/msr-index.h | 2 ++
arch/x86/mm/mem_encrypt.c | 9 -
arch/x86/mm/mem_encrypt_identity.c | 3 +++
4 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/mem_encrypt.h
b/arch/x86/include/asm/mem_encrypt.h
index 5049f6c22683..4e72b73a9cb5 100644
--- a/arch/x86/include/asm/mem_encrypt.h
+++ b/arch/x86/include/asm/mem_encrypt.h
@@ -19,6 +19,7 @@
#ifdef CONFIG_AMD_MEM_ENCRYPT
extern u64 sme_me_mask;
+extern u64 sev_status;
extern bool sev_enabled;
void sme_encrypt_execute(unsigned long encrypted_kernel_vaddr,
@@ -50,6 +51,7 @@ void __init mem_encrypt_init(void);
bool sme_active(void);
bool sev_active(void);
+bool sev_es_active(void);
#define __bss_decrypted __attribute__((__section__(".bss..decrypted")))
@@ -72,6 +74,7 @@ static inline void __init sme_enable(struct boot_params *bp)
{ }
static inline bool sme_active(void) { return false; }
static inline bool sev_active(void) { return false; }
+static inline bool sev_es_active(void) { return false; }
static inline int __init
early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return
0; }
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index cd6d651ff730..95871defba91 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -469,7 +469,9 @@
#define MSR_AMD64_SEV_ES_GHCB 0xc0010130
#define MSR_AMD64_SEV 0xc0010131
#define MSR_AMD64_SEV_ENABLED_BIT 0
+#define MSR_AMD64_SEV_ES_ENABLED_BIT 1
#define MSR_AMD64_SEV_ENABLED BIT_ULL(MSR_AMD64_SEV_ENABLED_BIT)
+#define MSR_AMD64_SEV_ES_ENABLED BIT_ULL(MSR_AMD64_SEV_ES_ENABLED_BIT)
#define MSR_AMD64_VIRT_SPEC_CTRL 0xc001011f
diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 9f1177edc2e7..232d6e1bcfc6 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c
@@ -38,6 +38,7 @@
* section is later cleared.
*/
u64 sme_me_mask __section(.data) = 0;
+u64 sev_status __section(.data) = 0;
EXPORT_SYMBOL(sme_me_mask);
DEFINE_STATIC_KEY_FALSE(sev_enable_key);
EXPORT_SYMBOL_GPL(sev_enable_key);
@@ -347,7 +348,13 @@ bool sme_active(void)
bool sev_active(void)
{
- return sme_me_mask && sev_enabled;
+ return !!(sev_status & MSR_AMD64_SEV_ENABLED);
+}
+
+/* Needs to be called from non-instrumentable code */
+bool noinstr sev_es_active(void)
+{
+ return !!(sev_status & MSR_AMD64_SEV_ES_ENABLED);
}
/* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */
diff --git a/arch/x86/mm/mem_encrypt_identity.c
b/arch/x86/mm/mem_encrypt_identity.c
index e2b0e2ac07bb..68d75379e06a 100644
--- a/arch/x86/mm/mem_encrypt_identity.c
+++ b/arch/x86/mm/mem_encrypt_identity.c
@@ -540,6 +540,9 @@ void __init sme_enable(struct boot_params *bp)
if (!(msr & MSR_AMD64_SEV_ENABLED))
return;
+ /* Save SEV_STATUS to avoid reading MSR again */
+ sev_status = msr;
+
/* SEV state cannot be controlled by a command line option */
sme_me_mask = me_mask;
sev_enabled = true;
--
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[PATCH v6 02/76] KVM: SVM: Add GHCB definitions
From: Tom Lendacky
Extend the vmcb_safe_area with SEV-ES fields and add a new
'struct ghcb' which will be used for guest-hypervisor communication.
Signed-off-by: Tom Lendacky
Signed-off-by: Joerg Roedel
---
arch/x86/include/asm/svm.h | 45 +-
arch/x86/kvm/svm/svm.c | 2 ++
2 files changed, 46 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 8a1f5382a4ea..094b8f8fb1d4 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -200,13 +200,56 @@ struct __attribute__ ((__packed__)) vmcb_save_area {
u64 br_to;
u64 last_excp_from;
u64 last_excp_to;
+
+ /*
+* The following part of the save area is valid only for
+* SEV-ES guests when referenced through the GHCB.
+*/
+ u8 reserved_7[104];
+ u64 reserved_8; /* rax already available at 0x01f8 */
+ u64 rcx;
+ u64 rdx;
+ u64 rbx;
+ u64 reserved_9; /* rsp already available at 0x01d8 */
+ u64 rbp;
+ u64 rsi;
+ u64 rdi;
+ u64 r8;
+ u64 r9;
+ u64 r10;
+ u64 r11;
+ u64 r12;
+ u64 r13;
+ u64 r14;
+ u64 r15;
+ u8 reserved_10[16];
+ u64 sw_exit_code;
+ u64 sw_exit_info_1;
+ u64 sw_exit_info_2;
+ u64 sw_scratch;
+ u8 reserved_11[56];
+ u64 xcr0;
+ u8 valid_bitmap[16];
+ u64 x87_state_gpa;
};
+struct ghcb {
+ struct vmcb_save_area save;
+ u8 reserved_save[2048 - sizeof(struct vmcb_save_area)];
+
+ u8 shared_buffer[2032];
+
+ u8 reserved_1[10];
+ u16 protocol_version; /* negotiated SEV-ES/GHCB protocol version */
+ u32 ghcb_usage;
+} __packed;
+
static inline void __unused_size_checks(void)
{
- BUILD_BUG_ON(sizeof(struct vmcb_save_area) != 0x298);
+ BUILD_BUG_ON(sizeof(struct vmcb_save_area) != 1032);
BUILD_BUG_ON(sizeof(struct vmcb_control_area) != 256);
+ BUILD_BUG_ON(sizeof(struct ghcb) != 4096);
}
struct __attribute__ ((__packed__)) vmcb {
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 03dd7bac8034..4368b66615c1 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4164,6 +4164,8 @@ static struct kvm_x86_init_ops svm_init_ops __initdata = {
static int __init svm_init(void)
{
+ __unused_size_checks();
+
return kvm_init(_init_ops, sizeof(struct vcpu_svm),
__alignof__(struct vcpu_svm), THIS_MODULE);
}
--
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[PATCH v6 06/76] x86/traps: Move pf error codes to
From: Joerg Roedel
Move the definition of the x86 page-fault error code bits to the new
header file asm/trap_pf.h. This makes it easier to include them into
pre-decompression boot code. No functional changes.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-6-j...@8bytes.org
---
arch/x86/include/asm/trap_pf.h | 24
arch/x86/include/asm/traps.h | 19 +--
2 files changed, 25 insertions(+), 18 deletions(-)
create mode 100644 arch/x86/include/asm/trap_pf.h
diff --git a/arch/x86/include/asm/trap_pf.h b/arch/x86/include/asm/trap_pf.h
new file mode 100644
index ..305bc1214aef
--- /dev/null
+++ b/arch/x86/include/asm/trap_pf.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_TRAP_PF_H
+#define _ASM_X86_TRAP_PF_H
+
+/*
+ * Page fault error code bits:
+ *
+ * bit 0 == 0: no page found 1: protection fault
+ * bit 1 == 0: read access 1: write access
+ * bit 2 == 0: kernel-mode access 1: user-mode access
+ * bit 3 == 1: use of reserved bit detected
+ * bit 4 == 1: fault was an instruction fetch
+ * bit 5 == 1: protection keys block access
+ */
+enum x86_pf_error_code {
+ X86_PF_PROT = 1 << 0,
+ X86_PF_WRITE= 1 << 1,
+ X86_PF_USER = 1 << 2,
+ X86_PF_RSVD = 1 << 3,
+ X86_PF_INSTR= 1 << 4,
+ X86_PF_PK = 1 << 5,
+};
+
+#endif /* _ASM_X86_TRAP_PF_H */
diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h
index 714b1a30e7b0..6a308355ea29 100644
--- a/arch/x86/include/asm/traps.h
+++ b/arch/x86/include/asm/traps.h
@@ -8,6 +8,7 @@
#include
#include
#include/* TRAP_TRACE, ... */
+#include
#ifdef CONFIG_X86_64
asmlinkage __visible notrace struct pt_regs *sync_regs(struct pt_regs *eregs);
@@ -41,22 +42,4 @@ void __noreturn handle_stack_overflow(const char *message,
unsigned long fault_address);
#endif
-/*
- * Page fault error code bits:
- *
- * bit 0 == 0: no page found 1: protection fault
- * bit 1 == 0: read access 1: write access
- * bit 2 == 0: kernel-mode access 1: user-mode access
- * bit 3 == 1: use of reserved bit detected
- * bit 4 == 1: fault was an instruction fetch
- * bit 5 == 1: protection keys block access
- */
-enum x86_pf_error_code {
- X86_PF_PROT = 1 << 0,
- X86_PF_WRITE= 1 << 1,
- X86_PF_USER = 1 << 2,
- X86_PF_RSVD = 1 << 3,
- X86_PF_INSTR= 1 << 4,
- X86_PF_PK = 1 << 5,
-};
#endif /* _ASM_X86_TRAPS_H */
--
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[PATCH v6 32/76] x86/head/64: Load GDT after switch to virtual addresses
From: Joerg Roedel Load the GDT right after switching to virtual addresses to make sure there is a defined GDT for exception handling. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20200724160336.5435-32-j...@8bytes.org --- arch/x86/kernel/head_64.S | 16 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 800053219054..f958d4e4ee08 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -166,6 +166,14 @@ SYM_CODE_START(secondary_startup_64) 1: UNWIND_HINT_EMPTY + /* +* We must switch to a new descriptor in kernel space for the GDT +* because soon the kernel won't have access anymore to the userspace +* addresses where we're currently running on. We have to do that here +* because in 32bit we couldn't load a 64bit linear address. +*/ + lgdtearly_gdt_descr(%rip) + /* Check if nx is implemented */ movl$0x8001, %eax cpuid @@ -193,14 +201,6 @@ SYM_CODE_START(secondary_startup_64) pushq $0 popfq - /* -* We must switch to a new descriptor in kernel space for the GDT -* because soon the kernel won't have access anymore to the userspace -* addresses where we're currently running on. We have to do that here -* because in 32bit we couldn't load a 64bit linear address. -*/ - lgdtearly_gdt_descr(%rip) - /* set up data segments */ xorl %eax,%eax movl %eax,%ds -- 2.28.0 ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
[PATCH v6 21/76] x86/boot/compressed/64: Check return value of kernel_ident_mapping_init()
From: Joerg Roedel
The function can fail to create an identity mapping, check for that
and bail out if it happens.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-21-j...@8bytes.org
---
arch/x86/boot/compressed/ident_map_64.c | 7 +--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/arch/x86/boot/compressed/ident_map_64.c
b/arch/x86/boot/compressed/ident_map_64.c
index b4f2a5f503cd..aa91bebc0fe9 100644
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -91,6 +91,8 @@ static struct x86_mapping_info mapping_info;
*/
static void add_identity_map(unsigned long start, unsigned long end)
{
+ int ret;
+
/* Align boundary to 2M. */
start = round_down(start, PMD_SIZE);
end = round_up(end, PMD_SIZE);
@@ -98,8 +100,9 @@ static void add_identity_map(unsigned long start, unsigned
long end)
return;
/* Build the mapping. */
- kernel_ident_mapping_init(_info, (pgd_t *)top_level_pgt,
- start, end);
+ ret = kernel_ident_mapping_init(_info, (pgd_t *)top_level_pgt,
start, end);
+ if (ret)
+ error("Error: kernel_ident_mapping_init() failed\n");
}
/* Locates and clears a region for a new top level page table. */
--
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[PATCH v6 34/76] x86/head/64: Switch to initial stack earlier
From: Joerg Roedel Make sure there is a stack once the kernel runs from virual addresses. At this stage any secondary CPU which boots will have lost its stack because the kernel switched to a new page-table which does not map the real-mode stack anymore. This is needed for handling early #VC exceptions caused by instructions like CPUID. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20200724160336.5435-34-j...@8bytes.org --- arch/x86/kernel/head_64.S | 9 ++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 057c7bd3eeb6..a5e1939d1dc9 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -200,6 +200,12 @@ SYM_CODE_START(secondary_startup_64) movlinitial_gs+4(%rip),%edx wrmsr + /* +* Setup a boot time stack - Any secondary CPU will have lost its stack +* by now because the cr3-switch above unmaps the real-mode stack +*/ + movq initial_stack(%rip), %rsp + /* Check if nx is implemented */ movl$0x8001, %eax cpuid @@ -220,9 +226,6 @@ SYM_CODE_START(secondary_startup_64) /* Make changes effective */ movq%rax, %cr0 - /* Setup a boot time stack */ - movq initial_stack(%rip), %rsp - /* zero EFLAGS after setting rsp */ pushq $0 popfq -- 2.28.0 ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
[PATCH v6 37/76] x86/head/64: Move early exception dispatch to C code
From: Joerg Roedel
Move the assembly coded dispatch between page-faults and all other
exceptions to C code to make it easier to maintain and extend.
Also change the return-type of early_make_pgtable() to bool and make it
static.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-37-j...@8bytes.org
---
arch/x86/include/asm/pgtable.h | 2 +-
arch/x86/include/asm/setup.h | 4 +++-
arch/x86/kernel/head64.c | 19 +++
arch/x86/kernel/head_64.S | 11 +--
4 files changed, 20 insertions(+), 16 deletions(-)
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 5e0dcc20614d..a02c67291cfc 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -28,7 +28,7 @@
#include
extern pgd_t early_top_pgt[PTRS_PER_PGD];
-int __init __early_make_pgtable(unsigned long address, pmdval_t pmd);
+bool __init __early_make_pgtable(unsigned long address, pmdval_t pmd);
void ptdump_walk_pgd_level(struct seq_file *m, struct mm_struct *mm);
void ptdump_walk_pgd_level_debugfs(struct seq_file *m, struct mm_struct *mm,
diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h
index 5c09f50ecf1c..cafae86813ae 100644
--- a/arch/x86/include/asm/setup.h
+++ b/arch/x86/include/asm/setup.h
@@ -39,6 +39,8 @@ void vsmp_init(void);
static inline void vsmp_init(void) { }
#endif
+struct pt_regs;
+
void setup_bios_corruption_check(void);
void early_platform_quirks(void);
@@ -49,9 +51,9 @@ extern void i386_reserve_resources(void);
extern unsigned long __startup_64(unsigned long physaddr, struct boot_params
*bp);
extern unsigned long __startup_secondary_64(void);
extern void startup_64_setup_env(unsigned long physbase);
-extern int early_make_pgtable(unsigned long address);
extern void early_idt_setup_early_handler(unsigned long physaddr);
extern void early_load_idt(void);
+extern void __init do_early_exception(struct pt_regs *regs, int trapnr);
#ifdef CONFIG_X86_INTEL_MID
extern void x86_intel_mid_early_setup(void);
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 096b09d06d1c..41514ec1e6f0 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -37,6 +37,8 @@
#include
#include
#include
+#include
+#include
/*
* Manage page tables very early on.
@@ -314,7 +316,7 @@ static void __init reset_early_page_tables(void)
}
/* Create a new PMD entry */
-int __init __early_make_pgtable(unsigned long address, pmdval_t pmd)
+bool __init __early_make_pgtable(unsigned long address, pmdval_t pmd)
{
unsigned long physaddr = address - __PAGE_OFFSET;
pgdval_t pgd, *pgd_p;
@@ -324,7 +326,7 @@ int __init __early_make_pgtable(unsigned long address,
pmdval_t pmd)
/* Invalid address or early pgt is done ? */
if (physaddr >= MAXMEM || read_cr3_pa() != __pa_nodebug(early_top_pgt))
- return -1;
+ return false;
again:
pgd_p = _top_pgt[pgd_index(address)].pgd;
@@ -381,10 +383,10 @@ int __init __early_make_pgtable(unsigned long address,
pmdval_t pmd)
}
pmd_p[pmd_index(address)] = pmd;
- return 0;
+ return true;
}
-int __init early_make_pgtable(unsigned long address)
+static bool __init early_make_pgtable(unsigned long address)
{
unsigned long physaddr = address - __PAGE_OFFSET;
pmdval_t pmd;
@@ -394,6 +396,15 @@ int __init early_make_pgtable(unsigned long address)
return __early_make_pgtable(address, pmd);
}
+void __init do_early_exception(struct pt_regs *regs, int trapnr)
+{
+ if (trapnr == X86_TRAP_PF &&
+ early_make_pgtable(native_read_cr2()))
+ return;
+
+ early_fixup_exception(regs, trapnr);
+}
+
/* Don't add a printk in there. printk relies on the PDA which is not
initialized
yet. */
static void __init clear_bss(void)
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 28de83fecda3..08412f308de3 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -349,18 +349,9 @@ SYM_CODE_START_LOCAL(early_idt_handler_common)
pushq %r15 /* pt_regs->r15 */
UNWIND_HINT_REGS
- cmpq $14,%rsi /* Page fault? */
- jnz 10f
- GET_CR2_INTO(%rdi) /* can clobber %rax if pv */
- call early_make_pgtable
- andl %eax,%eax
- jz 20f /* All good */
-
-10:
movq %rsp,%rdi /* RDI = pt_regs; RSI is already trapnr */
- call early_fixup_exception
+ call do_early_exception
-20:
decl early_recursion_flag(%rip)
jmp restore_regs_and_return_to_kernel
SYM_CODE_END(early_idt_handler_common)
--
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[PATCH v6 04/76] KVM: SVM: Use __packed shorthand
From: Borislav Petkov
Use the shorthand to make it more readable.
No functional changes.
Signed-off-by: Borislav Petkov
Signed-off-by: Joerg Roedel
---
arch/x86/include/asm/svm.h | 12 ++--
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 50e5fa8d3249..da38eb195355 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -150,14 +150,14 @@ struct __attribute__ ((__packed__)) vmcb_control_area {
#define SVM_NESTED_CTL_NP_ENABLE BIT(0)
#define SVM_NESTED_CTL_SEV_ENABLE BIT(1)
-struct __attribute__ ((__packed__)) vmcb_seg {
+struct vmcb_seg {
u16 selector;
u16 attrib;
u32 limit;
u64 base;
-};
+} __packed;
-struct __attribute__ ((__packed__)) vmcb_save_area {
+struct vmcb_save_area {
struct vmcb_seg es;
struct vmcb_seg cs;
struct vmcb_seg ss;
@@ -231,7 +231,7 @@ struct __attribute__ ((__packed__)) vmcb_save_area {
u64 xcr0;
u8 valid_bitmap[16];
u64 x87_state_gpa;
-};
+} __packed;
struct ghcb {
struct vmcb_save_area save;
@@ -252,11 +252,11 @@ static inline void __unused_size_checks(void)
BUILD_BUG_ON(sizeof(struct ghcb) != 4096);
}
-struct __attribute__ ((__packed__)) vmcb {
+struct vmcb {
struct vmcb_control_area control;
u8 reserved_control[1024 - sizeof(struct vmcb_control_area)];
struct vmcb_save_area save;
-};
+} __packed;
#define SVM_CPUID_FUNC 0x800a
--
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[PATCH v6 08/76] x86/umip: Factor out instruction fetch
From: Joerg Roedel
Factor out the code to fetch the instruction from user-space to a helper
function.
No functional changes.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-8-j...@8bytes.org
---
arch/x86/include/asm/insn-eval.h | 2 ++
arch/x86/kernel/umip.c | 26 +-
arch/x86/lib/insn-eval.c | 38
3 files changed, 46 insertions(+), 20 deletions(-)
diff --git a/arch/x86/include/asm/insn-eval.h b/arch/x86/include/asm/insn-eval.h
index 2b6ccf2c49f1..b8b9ef1bbd06 100644
--- a/arch/x86/include/asm/insn-eval.h
+++ b/arch/x86/include/asm/insn-eval.h
@@ -19,5 +19,7 @@ void __user *insn_get_addr_ref(struct insn *insn, struct
pt_regs *regs);
int insn_get_modrm_rm_off(struct insn *insn, struct pt_regs *regs);
unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx);
int insn_get_code_seg_params(struct pt_regs *regs);
+int insn_fetch_from_user(struct pt_regs *regs,
+unsigned char buf[MAX_INSN_SIZE]);
#endif /* _ASM_X86_INSN_EVAL_H */
diff --git a/arch/x86/kernel/umip.c b/arch/x86/kernel/umip.c
index 2c304fd0bb1a..ad135be4f1f0 100644
--- a/arch/x86/kernel/umip.c
+++ b/arch/x86/kernel/umip.c
@@ -335,11 +335,11 @@ static void force_sig_info_umip_fault(void __user *addr,
struct pt_regs *regs)
*/
bool fixup_umip_exception(struct pt_regs *regs)
{
- int not_copied, nr_copied, reg_offset, dummy_data_size, umip_inst;
- unsigned long seg_base = 0, *reg_addr;
+ int nr_copied, reg_offset, dummy_data_size, umip_inst;
/* 10 bytes is the maximum size of the result of UMIP instructions */
unsigned char dummy_data[10] = { 0 };
unsigned char buf[MAX_INSN_SIZE];
+ unsigned long *reg_addr;
void __user *uaddr;
struct insn insn;
int seg_defs;
@@ -347,26 +347,12 @@ bool fixup_umip_exception(struct pt_regs *regs)
if (!regs)
return false;
- /*
-* If not in user-space long mode, a custom code segment could be in
-* use. This is true in protected mode (if the process defined a local
-* descriptor table), or virtual-8086 mode. In most of the cases
-* seg_base will be zero as in USER_CS.
-*/
- if (!user_64bit_mode(regs))
- seg_base = insn_get_seg_base(regs, INAT_SEG_REG_CS);
-
- if (seg_base == -1L)
- return false;
-
- not_copied = copy_from_user(buf, (void __user *)(seg_base + regs->ip),
- sizeof(buf));
- nr_copied = sizeof(buf) - not_copied;
+ nr_copied = insn_fetch_from_user(regs, buf);
/*
-* The copy_from_user above could have failed if user code is protected
-* by a memory protection key. Give up on emulation in such a case.
-* Should we issue a page fault?
+* The insn_fetch_from_user above could have failed if user code
+* is protected by a memory protection key. Give up on emulation
+* in such a case. Should we issue a page fault?
*/
if (!nr_copied)
return false;
diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c
index 31600d851fd8..0c4f7ebc261b 100644
--- a/arch/x86/lib/insn-eval.c
+++ b/arch/x86/lib/insn-eval.c
@@ -1369,3 +1369,41 @@ void __user *insn_get_addr_ref(struct insn *insn, struct
pt_regs *regs)
return (void __user *)-1L;
}
}
+
+/**
+ * insn_fetch_from_user() - Copy instruction bytes from user-space memory
+ * @regs: Structure with register values as seen when entering kernel mode
+ * @buf: Array to store the fetched instruction
+ *
+ * Gets the linear address of the instruction and copies the instruction bytes
+ * to the buf.
+ *
+ * Returns:
+ *
+ * Number of instruction bytes copied.
+ *
+ * 0 if nothing was copied.
+ */
+int insn_fetch_from_user(struct pt_regs *regs, unsigned char
buf[MAX_INSN_SIZE])
+{
+ unsigned long seg_base = 0;
+ int not_copied;
+
+ /*
+* If not in user-space long mode, a custom code segment could be in
+* use. This is true in protected mode (if the process defined a local
+* descriptor table), or virtual-8086 mode. In most of the cases
+* seg_base will be zero as in USER_CS.
+*/
+ if (!user_64bit_mode(regs)) {
+ seg_base = insn_get_seg_base(regs, INAT_SEG_REG_CS);
+ if (seg_base == -1L)
+ return 0;
+ }
+
+
+ not_copied = copy_from_user(buf, (void __user *)(seg_base + regs->ip),
+ MAX_INSN_SIZE);
+
+ return MAX_INSN_SIZE - not_copied;
+}
--
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[PATCH v6 35/76] x86/head/64: Make fixup_pointer() static inline
From: Joerg Roedel
Also move it to a header file so that it can be used in the idt code
to setup the early IDT.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-35-j...@8bytes.org
---
arch/x86/include/asm/setup.h | 10 ++
arch/x86/kernel/head64.c | 5 -
2 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h
index 5c2fd05bd52c..8aa6ba0427b0 100644
--- a/arch/x86/include/asm/setup.h
+++ b/arch/x86/include/asm/setup.h
@@ -74,6 +74,16 @@ static inline void x86_ce4100_early_setup(void) { }
extern struct boot_params boot_params;
extern char _text[];
+/*
+ * This function is used in C code that runs while the kernel still runs on
+ * identity mapped addresses to get the correct address of kernel pointers in
+ * the identity mapping.
+ */
+static __always_inline void *fixup_pointer(void *ptr, unsigned long physaddr)
+{
+ return ptr - (void *)_text + (void *)physaddr;
+}
+
static inline bool kaslr_enabled(void)
{
return IS_ENABLED(CONFIG_RANDOMIZE_MEMORY) &&
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index b0ab5627900b..8703292a35e9 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -82,11 +82,6 @@ static struct desc_ptr startup_gdt_descr = {
#define __head __section(.head.text)
-static void __head *fixup_pointer(void *ptr, unsigned long physaddr)
-{
- return ptr - (void *)_text + (void *)physaddr;
-}
-
static unsigned long __head *fixup_long(void *ptr, unsigned long physaddr)
{
return fixup_pointer(ptr, physaddr);
--
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[PATCH v6 17/76] x86/boot/compressed/64: Don't pre-map memory in KASLR code
From: Joerg Roedel
With the page-fault handler in place the identity mapping can be built
on-demand. So remove the code which manually creates the mappings and
unexport/remove the functions used for it.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-17-j...@8bytes.org
---
arch/x86/boot/compressed/ident_map_64.c | 6 ++
arch/x86/boot/compressed/kaslr.c| 24 +---
arch/x86/boot/compressed/misc.h | 10 --
3 files changed, 3 insertions(+), 37 deletions(-)
diff --git a/arch/x86/boot/compressed/ident_map_64.c
b/arch/x86/boot/compressed/ident_map_64.c
index ecf9353b064d..c63257bf8373 100644
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -87,11 +87,9 @@ phys_addr_t physical_mask = (1ULL << __PHYSICAL_MASK_SHIFT)
- 1;
static struct x86_mapping_info mapping_info;
/*
- * Adds the specified range to what will become the new identity mappings.
- * Once all ranges have been added, the new mapping is activated by calling
- * finalize_identity_maps() below.
+ * Adds the specified range to the identity mappings.
*/
-void add_identity_map(unsigned long start, unsigned long size)
+static void add_identity_map(unsigned long start, unsigned long size)
{
unsigned long end = start + size;
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 9016f2268aa7..371b19a6357d 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -397,8 +397,6 @@ static void mem_avoid_init(unsigned long input, unsigned
long input_size,
*/
mem_avoid[MEM_AVOID_ZO_RANGE].start = input;
mem_avoid[MEM_AVOID_ZO_RANGE].size = (output + init_size) - input;
- add_identity_map(mem_avoid[MEM_AVOID_ZO_RANGE].start,
-mem_avoid[MEM_AVOID_ZO_RANGE].size);
/* Avoid initrd. */
initrd_start = (u64)boot_params->ext_ramdisk_image << 32;
@@ -416,15 +414,11 @@ static void mem_avoid_init(unsigned long input, unsigned
long input_size,
cmd_line_size = strnlen((char *)cmd_line, COMMAND_LINE_SIZE-1)
+ 1;
mem_avoid[MEM_AVOID_CMDLINE].start = cmd_line;
mem_avoid[MEM_AVOID_CMDLINE].size = cmd_line_size;
- add_identity_map(mem_avoid[MEM_AVOID_CMDLINE].start,
-mem_avoid[MEM_AVOID_CMDLINE].size);
}
/* Avoid boot parameters. */
mem_avoid[MEM_AVOID_BOOTPARAMS].start = (unsigned long)boot_params;
mem_avoid[MEM_AVOID_BOOTPARAMS].size = sizeof(*boot_params);
- add_identity_map(mem_avoid[MEM_AVOID_BOOTPARAMS].start,
-mem_avoid[MEM_AVOID_BOOTPARAMS].size);
/* We don't need to set a mapping for setup_data. */
@@ -433,11 +427,6 @@ static void mem_avoid_init(unsigned long input, unsigned
long input_size,
/* Enumerate the immovable memory regions */
num_immovable_mem = count_immovable_mem_regions();
-
-#ifdef CONFIG_X86_VERBOSE_BOOTUP
- /* Make sure video RAM can be used. */
- add_identity_map(0, PMD_SIZE);
-#endif
}
/*
@@ -884,19 +873,8 @@ void choose_random_location(unsigned long input,
warn("Physical KASLR disabled: no suitable memory region!");
} else {
/* Update the new physical address location. */
- if (*output != random_addr) {
- add_identity_map(random_addr, output_size);
+ if (*output != random_addr)
*output = random_addr;
- }
-
- /*
-* This loads the identity mapping page table.
-* This should only be done if a new physical address
-* is found for the kernel, otherwise we should keep
-* the old page table to make it be like the "nokaslr"
-* case.
-*/
- finalize_identity_maps();
}
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index f0e199174c5f..9840c82a39f1 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -98,17 +98,7 @@ static inline void choose_random_location(unsigned long
input,
#endif
#ifdef CONFIG_X86_64
-void initialize_identity_maps(void);
-void add_identity_map(unsigned long start, unsigned long size);
-void finalize_identity_maps(void);
extern unsigned char _pgtable[];
-#else
-static inline void initialize_identity_maps(void)
-{ }
-static inline void add_identity_map(unsigned long start, unsigned long size)
-{ }
-static inline void finalize_identity_maps(void)
-{ }
#endif
#ifdef CONFIG_EARLY_PRINTK
--
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[PATCH v6 29/76] x86/idt: Split idt_data setup out of set_intr_gate()
From: Joerg Roedel
The code to setup idt_data is needed for early exception handling, but
set_intr_gate() can't be used that early because it has pv-ops in its
code path, which don't work that early.
Split out the idt_data initialization part from set_intr_gate() so
that it can be used separatly.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-29-j...@8bytes.org
---
arch/x86/kernel/idt.c | 22 ++
1 file changed, 14 insertions(+), 8 deletions(-)
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index 34fcc58b81b5..c19773174221 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -205,18 +205,24 @@ idt_setup_from_table(gate_desc *idt, const struct
idt_data *t, int size, bool sy
}
}
+static void init_idt_data(struct idt_data *data, unsigned int n,
+ const void *addr)
+{
+ BUG_ON(n > 0xFF);
+
+ memset(data, 0, sizeof(*data));
+ data->vector= n;
+ data->addr = addr;
+ data->segment = __KERNEL_CS;
+ data->bits.type = GATE_INTERRUPT;
+ data->bits.p= 1;
+}
+
static __init void set_intr_gate(unsigned int n, const void *addr)
{
struct idt_data data;
- BUG_ON(n > 0xFF);
-
- memset(, 0, sizeof(data));
- data.vector = n;
- data.addr = addr;
- data.segment= __KERNEL_CS;
- data.bits.type = GATE_INTERRUPT;
- data.bits.p = 1;
+ init_idt_data(, n, addr);
idt_setup_from_table(idt_table, , 1, false);
}
--
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[PATCH v6 27/76] x86/sev-es: Add CPUID handling to #VC handler
From: Tom Lendacky
Handle #VC exceptions caused by CPUID instructions. These happen in
early boot code when the KASLR code checks for RDTSC.
Signed-off-by: Tom Lendacky
[ jroe...@suse.de: Adapt to #VC handling framework ]
Co-developed-by: Joerg Roedel
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-27-j...@8bytes.org
---
arch/x86/boot/compressed/sev-es.c | 4
arch/x86/kernel/sev-es-shared.c | 35 +++
2 files changed, 39 insertions(+)
diff --git a/arch/x86/boot/compressed/sev-es.c
b/arch/x86/boot/compressed/sev-es.c
index 4f2fc7a85c2f..851d7af29d79 100644
--- a/arch/x86/boot/compressed/sev-es.c
+++ b/arch/x86/boot/compressed/sev-es.c
@@ -16,6 +16,7 @@
#include
#include
#include
+#include
#include
#include
@@ -183,6 +184,9 @@ void do_boot_stage2_vc(struct pt_regs *regs, unsigned long
exit_code)
case SVM_EXIT_IOIO:
result = vc_handle_ioio(boot_ghcb, );
break;
+ case SVM_EXIT_CPUID:
+ result = vc_handle_cpuid(boot_ghcb, );
+ break;
default:
result = ES_UNSUPPORTED;
break;
diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c
index bae7cf28455b..a6b41910b8ab 100644
--- a/arch/x86/kernel/sev-es-shared.c
+++ b/arch/x86/kernel/sev-es-shared.c
@@ -432,3 +432,38 @@ static enum es_result vc_handle_ioio(struct ghcb *ghcb,
struct es_em_ctxt *ctxt)
return ret;
}
+
+static enum es_result vc_handle_cpuid(struct ghcb *ghcb,
+ struct es_em_ctxt *ctxt)
+{
+ struct pt_regs *regs = ctxt->regs;
+ u32 cr4 = native_read_cr4();
+ enum es_result ret;
+
+ ghcb_set_rax(ghcb, regs->ax);
+ ghcb_set_rcx(ghcb, regs->cx);
+
+ if (cr4 & X86_CR4_OSXSAVE)
+ /* Safe to read xcr0 */
+ ghcb_set_xcr0(ghcb, xgetbv(XCR_XFEATURE_ENABLED_MASK));
+ else
+ /* xgetbv will cause #GP - use reset value for xcr0 */
+ ghcb_set_xcr0(ghcb, 1);
+
+ ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_CPUID, 0, 0);
+ if (ret != ES_OK)
+ return ret;
+
+ if (!(ghcb_rax_is_valid(ghcb) &&
+ ghcb_rbx_is_valid(ghcb) &&
+ ghcb_rcx_is_valid(ghcb) &&
+ ghcb_rdx_is_valid(ghcb)))
+ return ES_VMM_ERROR;
+
+ regs->ax = ghcb->save.rax;
+ regs->bx = ghcb->save.rbx;
+ regs->cx = ghcb->save.rcx;
+ regs->dx = ghcb->save.rdx;
+
+ return ES_OK;
+}
--
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[PATCH v6 00/76] x86: SEV-ES Guest Support
From: Joerg Roedel Hi, here is the new version of the SEV-ES client enabling patch-set. It is based on the latest tip/master branch and contains the necessary changes. In particular those ar: - Enabling CR4.FSGSBASE early on supported processors so that early #VC exceptions on APs can be handled. - Add another patch (patch 1) to fix a KVM frame-size build warning on 32bit. The previous versions can be found as a linked-list starting here: https://lore.kernel.org/lkml/20200724160336.5435-1-j...@8bytes.org/ There you also find more detailed information about SEV-ES in general and its implications. Please review. Thanks, Joerg Borislav Petkov (1): KVM: SVM: Use __packed shorthand Doug Covelli (1): x86/vmware: Add VMware specific handling for VMMCALL under SEV-ES Joerg Roedel (54): KVM: SVM: nested: Don't allocate VMCB structures on stack KVM: SVM: Add GHCB Accessor functions x86/traps: Move pf error codes to x86/insn: Make inat-tables.c suitable for pre-decompression code x86/umip: Factor out instruction fetch x86/umip: Factor out instruction decoding x86/insn: Add insn_get_modrm_reg_off() x86/insn: Add insn_has_rep_prefix() helper x86/boot/compressed/64: Disable red-zone usage x86/boot/compressed/64: Add IDT Infrastructure x86/boot/compressed/64: Rename kaslr_64.c to ident_map_64.c x86/boot/compressed/64: Add page-fault handler x86/boot/compressed/64: Always switch to own page-table x86/boot/compressed/64: Don't pre-map memory in KASLR code x86/boot/compressed/64: Change add_identity_map() to take start and end x86/boot/compressed/64: Add stage1 #VC handler x86/boot/compressed/64: Call set_sev_encryption_mask earlier x86/boot/compressed/64: Check return value of kernel_ident_mapping_init() x86/boot/compressed/64: Add set_page_en/decrypted() helpers x86/boot/compressed/64: Setup GHCB Based VC Exception handler x86/boot/compressed/64: Unmap GHCB page before booting the kernel x86/fpu: Move xgetbv()/xsetbv() into separate header x86/idt: Move IDT to data segment x86/idt: Split idt_data setup out of set_intr_gate() x86/head/64: Install startup GDT x86/head/64: Setup MSR_GS_BASE before calling into C code x86/head/64: Load GDT after switch to virtual addresses x86/head/64: Load segment registers earlier x86/head/64: Switch to initial stack earlier x86/head/64: Make fixup_pointer() static inline x86/head/64: Load IDT earlier x86/head/64: Move early exception dispatch to C code x86/head/64: Set CR4.FSGSBASE early x86/sev-es: Add SEV-ES Feature Detection x86/sev-es: Print SEV-ES info into kernel log x86/sev-es: Compile early handler code into kernel image x86/sev-es: Setup early #VC handler x86/sev-es: Setup GHCB based boot #VC handler x86/sev-es: Allocate and Map IST stack for #VC handler x86/sev-es: Adjust #VC IST Stack on entering NMI handler x86/dumpstack/64: Add noinstr version of get_stack_info() x86/entry/64: Add entry code for #VC handler x86/sev-es: Wire up existing #VC exit-code handlers x86/sev-es: Handle instruction fetches from user-space x86/sev-es: Handle MMIO String Instructions x86/sev-es: Handle #AC Events x86/sev-es: Handle #DB Events x86/paravirt: Allow hypervisor specific VMMCALL handling under SEV-ES x86/realmode: Add SEV-ES specific trampoline entry point x86/smpboot: Setup TSS for starting AP x86/head/64: Don't call verify_cpu() on starting APs x86/head/64: Rename start_cpu0 x86/sev-es: Support CPU offline/online x86/sev-es: Handle NMI State Martin Radev (1): x86/sev-es: Check required CPU features for SEV-ES Tom Lendacky (19): KVM: SVM: Add GHCB definitions x86/cpufeatures: Add SEV-ES CPU feature x86/sev-es: Add support for handling IOIO exceptions x86/sev-es: Add CPUID handling to #VC handler x86/sev-es: Setup per-cpu GHCBs for the runtime handler x86/sev-es: Add Runtime #VC Exception Handler x86/sev-es: Handle MMIO events x86/sev-es: Handle MSR events x86/sev-es: Handle DR7 read/write events x86/sev-es: Handle WBINVD Events x86/sev-es: Handle RDTSC(P) Events x86/sev-es: Handle RDPMC Events x86/sev-es: Handle INVD Events x86/sev-es: Handle MONITOR/MONITORX Events x86/sev-es: Handle MWAIT/MWAITX Events x86/sev-es: Handle VMMCALL Events x86/kvm: Add KVM specific VMMCALL handling under SEV-ES x86/realmode: Setup AP jump table x86/efi: Add GHCB mappings when SEV-ES is active arch/x86/Kconfig |1 + arch/x86/boot/compressed/Makefile |9 +- arch/x86/boot/compressed/cpuflags.c|4 - arch/x86/boot/compressed/head_64.S | 32 +- arch/x86/boot/compressed/ident_map_64.c| 349 + arch/x86/boot/compressed/idt_64.c | 54 + arch/x86/boot/compressed/idt_handlers_64.S | 77 ++ arch/x86/boot/compressed/kaslr.c | 36 +- arch/x86/boot/compressed/kaslr_64.c| 153 ---
[PATCH v6 36/76] x86/head/64: Load IDT earlier
From: Joerg Roedel
Load the IDT right after switching to virtual addresses in head_64.S
so that the kernel can handle #VC exceptions.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-36-j...@8bytes.org
---
arch/x86/include/asm/setup.h | 3 +++
arch/x86/kernel/head64.c | 3 +++
arch/x86/kernel/head_64.S| 5 +
arch/x86/kernel/idt.c| 23 +++
4 files changed, 34 insertions(+)
diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h
index 8aa6ba0427b0..5c09f50ecf1c 100644
--- a/arch/x86/include/asm/setup.h
+++ b/arch/x86/include/asm/setup.h
@@ -50,6 +50,8 @@ extern unsigned long __startup_64(unsigned long physaddr,
struct boot_params *bp
extern unsigned long __startup_secondary_64(void);
extern void startup_64_setup_env(unsigned long physbase);
extern int early_make_pgtable(unsigned long address);
+extern void early_idt_setup_early_handler(unsigned long physaddr);
+extern void early_load_idt(void);
#ifdef CONFIG_X86_INTEL_MID
extern void x86_intel_mid_early_setup(void);
@@ -66,6 +68,7 @@ static inline void x86_ce4100_early_setup(void) { }
#ifndef _SETUP
#include
+#include
#include
/*
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 8703292a35e9..096b09d06d1c 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -286,6 +286,9 @@ unsigned long __head __startup_64(unsigned long physaddr,
}
}
+ /* Setup IDT with early handlers */
+ early_idt_setup_early_handler(physaddr);
+
/*
* Return the SME encryption mask (if SME is active) to be used as a
* modifier for the initial pgdir entry programmed into CR3.
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index a5e1939d1dc9..28de83fecda3 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -206,6 +206,11 @@ SYM_CODE_START(secondary_startup_64)
*/
movq initial_stack(%rip), %rsp
+ /* Load IDT */
+ pushq %rsi
+ callearly_load_idt
+ popq%rsi
+
/* Check if nx is implemented */
movl$0x8001, %eax
cpuid
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index c19773174221..e2777cc264f5 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -10,6 +10,7 @@
#include
#include
#include
+#include
struct idt_data {
unsigned intvector;
@@ -385,3 +386,25 @@ void __init alloc_intr_gate(unsigned int n, const void
*addr)
if (!WARN_ON(test_and_set_bit(n, system_vectors)))
set_intr_gate(n, addr);
}
+
+void __init early_idt_setup_early_handler(unsigned long physaddr)
+{
+ gate_desc *idt;
+ int i;
+
+ idt = fixup_pointer(idt_table, physaddr);
+
+ for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) {
+ struct idt_data data;
+ gate_desc desc;
+
+ init_idt_data(, i, early_idt_handler_array[i]);
+ idt_init_desc(, );
+ native_write_idt_entry(idt, i, );
+ }
+}
+
+void early_load_idt(void)
+{
+ load_idt(_descr);
+}
--
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Re: [PATCH v6 02/76] KVM: SVM: Add GHCB definitions
On Mon, Aug 24, 2020 at 10:53:57AM +0200, Joerg Roedel wrote:
> static inline void __unused_size_checks(void)
> {
> - BUILD_BUG_ON(sizeof(struct vmcb_save_area) != 0x298);
> + BUILD_BUG_ON(sizeof(struct vmcb_save_area) != 1032);
> BUILD_BUG_ON(sizeof(struct vmcb_control_area) != 256);
> + BUILD_BUG_ON(sizeof(struct ghcb) != 4096);
Could those naked numbers be proper, meaningfully named defines?
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
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[PATCH v6 19/76] x86/boot/compressed/64: Add stage1 #VC handler
From: Joerg Roedel
Add the first handler for #VC exceptions. At stage 1 there is no GHCB
yet becaue the kernel might still be running on the EFI page table.
The stage 1 handler is limited to the MSR based protocol to talk to
the hypervisor and can only support CPUID exit-codes, but that is
enough to get to stage 2.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-19-j...@8bytes.org
---
arch/x86/boot/compressed/Makefile | 1 +
arch/x86/boot/compressed/idt_64.c | 4 ++
arch/x86/boot/compressed/idt_handlers_64.S | 4 ++
arch/x86/boot/compressed/misc.h| 1 +
arch/x86/boot/compressed/sev-es.c | 45 +++
arch/x86/include/asm/msr-index.h | 1 +
arch/x86/include/asm/sev-es.h | 37
arch/x86/include/asm/trapnr.h | 1 +
arch/x86/kernel/sev-es-shared.c| 66 ++
9 files changed, 160 insertions(+)
create mode 100644 arch/x86/boot/compressed/sev-es.c
create mode 100644 arch/x86/include/asm/sev-es.h
create mode 100644 arch/x86/kernel/sev-es-shared.c
diff --git a/arch/x86/boot/compressed/Makefile
b/arch/x86/boot/compressed/Makefile
index 822e61a0d51b..a7b8c6e59e58 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -81,6 +81,7 @@ ifdef CONFIG_X86_64
vmlinux-objs-y += $(obj)/idt_64.o $(obj)/idt_handlers_64.o
vmlinux-objs-y += $(obj)/mem_encrypt.o
vmlinux-objs-y += $(obj)/pgtable_64.o
+ vmlinux-objs-$(CONFIG_AMD_MEM_ENCRYPT) += $(obj)/sev-es.o
endif
vmlinux-objs-$(CONFIG_ACPI) += $(obj)/acpi.o
diff --git a/arch/x86/boot/compressed/idt_64.c
b/arch/x86/boot/compressed/idt_64.c
index 5f083092a86d..f3ca7324be44 100644
--- a/arch/x86/boot/compressed/idt_64.c
+++ b/arch/x86/boot/compressed/idt_64.c
@@ -32,6 +32,10 @@ void load_stage1_idt(void)
{
boot_idt_desc.address = (unsigned long)boot_idt;
+
+ if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT))
+ set_idt_entry(X86_TRAP_VC, boot_stage1_vc);
+
load_boot_idt(_idt_desc);
}
diff --git a/arch/x86/boot/compressed/idt_handlers_64.S
b/arch/x86/boot/compressed/idt_handlers_64.S
index b20e57504a94..92eb4df478a1 100644
--- a/arch/x86/boot/compressed/idt_handlers_64.S
+++ b/arch/x86/boot/compressed/idt_handlers_64.S
@@ -70,3 +70,7 @@ SYM_FUNC_END(\name)
.code64
EXCEPTION_HANDLER boot_page_fault do_boot_page_fault error_code=1
+
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+EXCEPTION_HANDLER boot_stage1_vc do_vc_no_ghcb error_code=1
+#endif
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 9840c82a39f1..eaa8b45ebccb 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -141,5 +141,6 @@ extern struct desc_ptr boot_idt_desc;
/* IDT Entry Points */
void boot_page_fault(void);
+void boot_stage1_vc(void);
#endif /* BOOT_COMPRESSED_MISC_H */
diff --git a/arch/x86/boot/compressed/sev-es.c
b/arch/x86/boot/compressed/sev-es.c
new file mode 100644
index ..bb91cbb5920e
--- /dev/null
+++ b/arch/x86/boot/compressed/sev-es.c
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AMD Encrypted Register State Support
+ *
+ * Author: Joerg Roedel
+ */
+
+/*
+ * misc.h needs to be first because it knows how to include the other kernel
+ * headers in the pre-decompression code in a way that does not break
+ * compilation.
+ */
+#include "misc.h"
+
+#include
+#include
+#include
+#include
+
+static inline u64 sev_es_rd_ghcb_msr(void)
+{
+ unsigned long low, high;
+
+ asm volatile("rdmsr\n" : "=a" (low), "=d" (high) :
+ "c" (MSR_AMD64_SEV_ES_GHCB));
+
+ return ((high << 32) | low);
+}
+
+static inline void sev_es_wr_ghcb_msr(u64 val)
+{
+ u32 low, high;
+
+ low = val & 0xUL;
+ high = val >> 32;
+
+ asm volatile("wrmsr\n" : : "c" (MSR_AMD64_SEV_ES_GHCB),
+ "a"(low), "d" (high) : "memory");
+}
+
+#undef __init
+#define __init
+
+/* Include code for early handlers */
+#include "../../kernel/sev-es-shared.c"
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index dc131b84ac3a..cd6d651ff730 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -466,6 +466,7 @@
#define MSR_AMD64_IBSBRTARGET 0xc001103b
#define MSR_AMD64_IBSOPDATA4 0xc001103d
#define MSR_AMD64_IBS_REG_COUNT_MAX8 /* includes MSR_AMD64_IBSBRTARGET */
+#define MSR_AMD64_SEV_ES_GHCB 0xc0010130
#define MSR_AMD64_SEV 0xc0010131
#define MSR_AMD64_SEV_ENABLED_BIT 0
#define MSR_AMD64_SEV_ENABLED BIT_ULL(MSR_AMD64_SEV_ENABLED_BIT)
diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h
new file mode 100644
index ..5d49a8a429d3
--- /dev/null
+++ b/arch/x86/include/asm/sev-es.h
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier:
[PATCH v6 01/76] KVM: SVM: nested: Don't allocate VMCB structures on stack
From: Joerg Roedel
Do not allocate a vmcb_control_area and a vmcb_save_area on the stack,
as these structures will become larger with future extenstions of
SVM and thus the svm_set_nested_state() function will become a too large
stack frame.
Signed-off-by: Joerg Roedel
---
arch/x86/kvm/svm/nested.c | 47 +++
1 file changed, 33 insertions(+), 14 deletions(-)
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index fb68467e6049..28036629abf8 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -1060,10 +1060,14 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
struct vmcb *hsave = svm->nested.hsave;
struct vmcb __user *user_vmcb = (struct vmcb __user *)
_kvm_nested_state->data.svm[0];
- struct vmcb_control_area ctl;
- struct vmcb_save_area save;
+ struct vmcb_control_area *ctl;
+ struct vmcb_save_area *save;
+ int ret;
u32 cr0;
+ BUILD_BUG_ON(sizeof(struct vmcb_control_area) + sizeof(struct
vmcb_save_area) >
+KVM_STATE_NESTED_SVM_VMCB_SIZE);
+
if (kvm_state->format != KVM_STATE_NESTED_FORMAT_SVM)
return -EINVAL;
@@ -1095,13 +1099,22 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
return -EINVAL;
if (kvm_state->size < sizeof(*kvm_state) +
KVM_STATE_NESTED_SVM_VMCB_SIZE)
return -EINVAL;
- if (copy_from_user(, _vmcb->control, sizeof(ctl)))
- return -EFAULT;
- if (copy_from_user(, _vmcb->save, sizeof(save)))
- return -EFAULT;
- if (!nested_vmcb_check_controls())
- return -EINVAL;
+ ret = -ENOMEM;
+ ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
+ save = kzalloc(sizeof(*save), GFP_KERNEL);
+ if (!ctl || !save)
+ goto out_free;
+
+ ret = -EFAULT;
+ if (copy_from_user(ctl, _vmcb->control, sizeof(*ctl)))
+ goto out_free;
+ if (copy_from_user(save, _vmcb->save, sizeof(*save)))
+ goto out_free;
+
+ ret = -EINVAL;
+ if (!nested_vmcb_check_controls(ctl))
+ goto out_free;
/*
* Processor state contains L2 state. Check that it is
@@ -1109,15 +1122,15 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
*/
cr0 = kvm_read_cr0(vcpu);
if (((cr0 & X86_CR0_CD) == 0) && (cr0 & X86_CR0_NW))
-return -EINVAL;
+ goto out_free;
/*
* Validate host state saved from before VMRUN (see
* nested_svm_check_permissions).
* TODO: validate reserved bits for all saved state.
*/
- if (!(save.cr0 & X86_CR0_PG))
- return -EINVAL;
+ if (!(save->cr0 & X86_CR0_PG))
+ goto out_free;
/*
* All checks done, we can enter guest mode. L1 control fields
@@ -1126,15 +1139,21 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
* contains saved L1 state.
*/
copy_vmcb_control_area(>control, >vmcb->control);
- hsave->save = save;
+ hsave->save = *save;
svm->nested.vmcb = kvm_state->hdr.svm.vmcb_pa;
- load_nested_vmcb_control(svm, );
+ load_nested_vmcb_control(svm, ctl);
nested_prepare_vmcb_control(svm);
out_set_gif:
svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET));
- return 0;
+
+ ret = 0;
+out_free:
+ kfree(save);
+ kfree(ctl);
+
+ return ret;
}
struct kvm_x86_nested_ops svm_nested_ops = {
--
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[PATCH v6 24/76] x86/boot/compressed/64: Unmap GHCB page before booting the kernel
From: Joerg Roedel
Force a page-fault on any further accesses to the GHCB page when they
shouldn't happen anymore. This will catch the bugs where a #VC exception
is raised when no one is expected anymore.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-24-j...@8bytes.org
---
arch/x86/boot/compressed/ident_map_64.c | 17 +++--
arch/x86/boot/compressed/misc.h | 6 ++
arch/x86/boot/compressed/sev-es.c | 14 ++
3 files changed, 35 insertions(+), 2 deletions(-)
diff --git a/arch/x86/boot/compressed/ident_map_64.c
b/arch/x86/boot/compressed/ident_map_64.c
index 05742f641a06..063a60edcf99 100644
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -298,6 +298,11 @@ int set_page_encrypted(unsigned long address)
return set_clr_page_flags(_info, address, _PAGE_ENC, 0);
}
+int set_page_non_present(unsigned long address)
+{
+ return set_clr_page_flags(_info, address, 0, _PAGE_PRESENT);
+}
+
static void do_pf_error(const char *msg, unsigned long error_code,
unsigned long address, unsigned long ip)
{
@@ -316,8 +321,14 @@ static void do_pf_error(const char *msg, unsigned long
error_code,
void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code)
{
- unsigned long address = native_read_cr2() & PMD_MASK;
- unsigned long end = address + PMD_SIZE;
+ unsigned long address = native_read_cr2();
+ unsigned long end;
+ bool ghcb_fault;
+
+ ghcb_fault = sev_es_check_ghcb_fault(address);
+
+ address &= PMD_MASK;
+ end= address + PMD_SIZE;
/*
* Check for unexpected error codes. Unexpected are:
@@ -327,6 +338,8 @@ void do_boot_page_fault(struct pt_regs *regs, unsigned long
error_code)
*/
if (error_code & (X86_PF_PROT | X86_PF_USER | X86_PF_RSVD))
do_pf_error("Unexpected page-fault:", error_code, address,
regs->ip);
+ else if (ghcb_fault)
+ do_pf_error("Page-fault on GHCB page:", error_code, address,
regs->ip);
/*
* Error code is sane - now identity map the 2M region around
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 9995c70ca813..c0e0ffeee50a 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -100,6 +100,7 @@ static inline void choose_random_location(unsigned long
input,
#ifdef CONFIG_X86_64
extern int set_page_decrypted(unsigned long address);
extern int set_page_encrypted(unsigned long address);
+extern int set_page_non_present(unsigned long address);
extern unsigned char _pgtable[];
#endif
@@ -117,8 +118,13 @@ void set_sev_encryption_mask(void);
#ifdef CONFIG_AMD_MEM_ENCRYPT
void sev_es_shutdown_ghcb(void);
+extern bool sev_es_check_ghcb_fault(unsigned long address);
#else
static inline void sev_es_shutdown_ghcb(void) { }
+static inline bool sev_es_check_ghcb_fault(unsigned long address)
+{
+ return false;
+}
#endif
/* acpi.c */
diff --git a/arch/x86/boot/compressed/sev-es.c
b/arch/x86/boot/compressed/sev-es.c
index 7e2cec170026..e3abf8737015 100644
--- a/arch/x86/boot/compressed/sev-es.c
+++ b/arch/x86/boot/compressed/sev-es.c
@@ -121,6 +121,20 @@ void sev_es_shutdown_ghcb(void)
*/
if (set_page_encrypted((unsigned long)_ghcb_page))
error("Can't map GHCB page encrypted");
+
+ /*
+* GHCB page is mapped encrypted again and flushed from the cache.
+* Mark it non-present now to catch bugs when #VC exceptions trigger
+* after this point.
+*/
+ if (set_page_non_present((unsigned long)_ghcb_page))
+ error("Can't unmap GHCB page");
+}
+
+bool sev_es_check_ghcb_fault(unsigned long address)
+{
+ /* Check whether the fault was on the GHCB page */
+ return ((address & PAGE_MASK) == (unsigned long)_ghcb_page);
}
void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code)
--
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[PATCH v6 10/76] x86/insn: Add insn_get_modrm_reg_off()
From: Joerg Roedel
Add a function to the instruction decoder which returns the pt_regs
offset of the register specified in the reg field of the modrm byte.
Signed-off-by: Joerg Roedel
Acked-by: Masami Hiramatsu
Link: https://lore.kernel.org/r/20200724160336.5435-10-j...@8bytes.org
---
arch/x86/include/asm/insn-eval.h | 1 +
arch/x86/lib/insn-eval.c | 23 +++
2 files changed, 24 insertions(+)
diff --git a/arch/x86/include/asm/insn-eval.h b/arch/x86/include/asm/insn-eval.h
index 392b4fe377f9..f748f57f1491 100644
--- a/arch/x86/include/asm/insn-eval.h
+++ b/arch/x86/include/asm/insn-eval.h
@@ -17,6 +17,7 @@
void __user *insn_get_addr_ref(struct insn *insn, struct pt_regs *regs);
int insn_get_modrm_rm_off(struct insn *insn, struct pt_regs *regs);
+int insn_get_modrm_reg_off(struct insn *insn, struct pt_regs *regs);
unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx);
int insn_get_code_seg_params(struct pt_regs *regs);
int insn_fetch_from_user(struct pt_regs *regs,
diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c
index f52046f90dd3..a8ac5c5e94f0 100644
--- a/arch/x86/lib/insn-eval.c
+++ b/arch/x86/lib/insn-eval.c
@@ -20,6 +20,7 @@
enum reg_type {
REG_TYPE_RM = 0,
+ REG_TYPE_REG,
REG_TYPE_INDEX,
REG_TYPE_BASE,
};
@@ -441,6 +442,13 @@ static int get_reg_offset(struct insn *insn, struct
pt_regs *regs,
regno += 8;
break;
+ case REG_TYPE_REG:
+ regno = X86_MODRM_REG(insn->modrm.value);
+
+ if (X86_REX_R(insn->rex_prefix.value))
+ regno += 8;
+ break;
+
case REG_TYPE_INDEX:
regno = X86_SIB_INDEX(insn->sib.value);
if (X86_REX_X(insn->rex_prefix.value))
@@ -809,6 +817,21 @@ int insn_get_modrm_rm_off(struct insn *insn, struct
pt_regs *regs)
return get_reg_offset(insn, regs, REG_TYPE_RM);
}
+/**
+ * insn_get_modrm_reg_off() - Obtain register in reg part of the ModRM byte
+ * @insn: Instruction containing the ModRM byte
+ * @regs: Register values as seen when entering kernel mode
+ *
+ * Returns:
+ *
+ * The register indicated by the reg part of the ModRM byte. The
+ * register is obtained as an offset from the base of pt_regs.
+ */
+int insn_get_modrm_reg_off(struct insn *insn, struct pt_regs *regs)
+{
+ return get_reg_offset(insn, regs, REG_TYPE_REG);
+}
+
/**
* get_seg_base_limit() - obtain base address and limit of a segment
* @insn: Instruction. Must be valid.
--
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[PATCH v6 15/76] x86/boot/compressed/64: Add page-fault handler
From: Joerg Roedel
Install a page-fault handler to add an identity mapping to addresses
not yet mapped. Also do some checking whether the error code is sane.
This makes non SEV-ES machines use the exception handling
infrastructure in the pre-decompressions boot code too, making it less
likely to break in the future.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-15-j...@8bytes.org
---
arch/x86/boot/compressed/ident_map_64.c| 39 ++
arch/x86/boot/compressed/idt_64.c | 2 ++
arch/x86/boot/compressed/idt_handlers_64.S | 2 ++
arch/x86/boot/compressed/misc.h| 6
4 files changed, 49 insertions(+)
diff --git a/arch/x86/boot/compressed/ident_map_64.c
b/arch/x86/boot/compressed/ident_map_64.c
index d9932a133ac9..e3d980ae9c2b 100644
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -19,10 +19,13 @@
/* No PAGE_TABLE_ISOLATION support needed either: */
#undef CONFIG_PAGE_TABLE_ISOLATION
+#include "error.h"
#include "misc.h"
/* These actually do the work of building the kernel identity maps. */
#include
+#include
+#include
#include
/* Use the static base for this part of the boot process */
#undef __PAGE_OFFSET
@@ -160,3 +163,39 @@ void finalize_identity_maps(void)
{
write_cr3(top_level_pgt);
}
+
+static void do_pf_error(const char *msg, unsigned long error_code,
+ unsigned long address, unsigned long ip)
+{
+ error_putstr(msg);
+
+ error_putstr("\nError Code: ");
+ error_puthex(error_code);
+ error_putstr("\nCR2: 0x");
+ error_puthex(address);
+ error_putstr("\nRIP relative to _head: 0x");
+ error_puthex(ip - (unsigned long)_head);
+ error_putstr("\n");
+
+ error("Stopping.\n");
+}
+
+void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code)
+{
+ unsigned long address = native_read_cr2();
+
+ /*
+* Check for unexpected error codes. Unexpected are:
+* - Faults on present pages
+* - User faults
+* - Reserved bits set
+*/
+ if (error_code & (X86_PF_PROT | X86_PF_USER | X86_PF_RSVD))
+ do_pf_error("Unexpected page-fault:", error_code, address,
regs->ip);
+
+ /*
+* Error code is sane - now identity map the 2M region around
+* the faulting address.
+*/
+ add_identity_map(address & PMD_MASK, PMD_SIZE);
+}
diff --git a/arch/x86/boot/compressed/idt_64.c
b/arch/x86/boot/compressed/idt_64.c
index 082cd6bca033..5f083092a86d 100644
--- a/arch/x86/boot/compressed/idt_64.c
+++ b/arch/x86/boot/compressed/idt_64.c
@@ -40,5 +40,7 @@ void load_stage2_idt(void)
{
boot_idt_desc.address = (unsigned long)boot_idt;
+ set_idt_entry(X86_TRAP_PF, boot_page_fault);
+
load_boot_idt(_idt_desc);
}
diff --git a/arch/x86/boot/compressed/idt_handlers_64.S
b/arch/x86/boot/compressed/idt_handlers_64.S
index 36dee2f40a8b..b20e57504a94 100644
--- a/arch/x86/boot/compressed/idt_handlers_64.S
+++ b/arch/x86/boot/compressed/idt_handlers_64.S
@@ -68,3 +68,5 @@ SYM_FUNC_END(\name)
.text
.code64
+
+EXCEPTION_HANDLER boot_page_fault do_boot_page_fault error_code=1
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 98b7a1df9c59..f0e199174c5f 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -37,6 +37,9 @@
#define memptr unsigned
#endif
+/* boot/compressed/vmlinux start and end markers */
+extern char _head[], _end[];
+
/* misc.c */
extern memptr free_mem_ptr;
extern memptr free_mem_end_ptr;
@@ -146,4 +149,7 @@ extern pteval_t __default_kernel_pte_mask;
extern gate_desc boot_idt[BOOT_IDT_ENTRIES];
extern struct desc_ptr boot_idt_desc;
+/* IDT Entry Points */
+void boot_page_fault(void);
+
#endif /* BOOT_COMPRESSED_MISC_H */
--
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[PATCH v6 05/76] x86/cpufeatures: Add SEV-ES CPU feature
From: Tom Lendacky
Add CPU feature detection for Secure Encrypted Virtualization with
Encrypted State. This feature enhances SEV by also encrypting the
guest register state, making it in-accessible to the hypervisor.
Signed-off-by: Tom Lendacky
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-5-j...@8bytes.org
---
arch/x86/include/asm/cpufeatures.h | 1 +
arch/x86/kernel/cpu/amd.c | 3 ++-
arch/x86/kernel/cpu/scattered.c| 1 +
3 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/cpufeatures.h
b/arch/x86/include/asm/cpufeatures.h
index 2901d5df4366..0bdaf2515892 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -236,6 +236,7 @@
#define X86_FEATURE_EPT_AD ( 8*32+17) /* Intel Extended Page Table
access-dirty bit */
#define X86_FEATURE_VMCALL ( 8*32+18) /* "" Hypervisor supports
the VMCALL instruction */
#define X86_FEATURE_VMW_VMMCALL( 8*32+19) /* "" VMware prefers
VMMCALL hypercall instruction */
+#define X86_FEATURE_SEV_ES ( 8*32+20) /* AMD Secure Encrypted
Virtualization - Encrypted State */
/* Intel-defined CPU features, CPUID level 0x0007:0 (EBX), word 9 */
#define X86_FEATURE_FSGSBASE ( 9*32+ 0) /* RDFSBASE, WRFSBASE,
RDGSBASE, WRGSBASE instructions*/
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index dcc3d943c68f..6062ce586b95 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -614,7 +614,7 @@ static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
*If BIOS has not enabled SME then don't advertise the
*SME feature (set in scattered.c).
* For SEV: If BIOS has not enabled SEV then don't advertise the
-*SEV feature (set in scattered.c).
+*SEV and SEV_ES feature (set in scattered.c).
*
* In all cases, since support for SME and SEV requires long mode,
* don't advertise the feature under CONFIG_X86_32.
@@ -645,6 +645,7 @@ static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
setup_clear_cpu_cap(X86_FEATURE_SME);
clear_sev:
setup_clear_cpu_cap(X86_FEATURE_SEV);
+ setup_clear_cpu_cap(X86_FEATURE_SEV_ES);
}
}
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index 62b137c3c97a..30f354989cf1 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -41,6 +41,7 @@ static const struct cpuid_bit cpuid_bits[] = {
{ X86_FEATURE_MBA, CPUID_EBX, 6, 0x8008, 0 },
{ X86_FEATURE_SME, CPUID_EAX, 0, 0x801f, 0 },
{ X86_FEATURE_SEV, CPUID_EAX, 1, 0x801f, 0 },
+ { X86_FEATURE_SEV_ES, CPUID_EAX, 3, 0x801f, 0 },
{ 0, 0, 0, 0, 0 }
};
--
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[PATCH v6 12/76] x86/boot/compressed/64: Disable red-zone usage
From: Joerg Roedel The x86-64 ABI defines a red-zone on the stack: The 128-byte area beyond the location pointed to by %rsp is considered to be reserved and shall not be modified by signal or interrupt handlers. Therefore, functions may use this area for temporary data that is not needed across function calls. In particular, leaf functions may use this area for their entire stack frame, rather than adjusting the stack pointer in the prologue and epilogue. This area is known as the red zone. This is not compatible with exception handling, because the IRET frame written by the hardware at the stack pointer and the functions to handle the exception will overwrite the temporary variables of the interrupted function, causing undefined behavior. So disable red-zones for the pre-decompression boot code. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20200724160336.5435-12-j...@8bytes.org --- arch/x86/boot/compressed/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 753d57266757..0acdaa8a7dab 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -32,7 +32,7 @@ KBUILD_CFLAGS := -m$(BITS) -O2 KBUILD_CFLAGS += -fno-strict-aliasing -fPIE KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING cflags-$(CONFIG_X86_32) := -march=i386 -cflags-$(CONFIG_X86_64) := -mcmodel=small +cflags-$(CONFIG_X86_64) := -mcmodel=small -mno-red-zone KBUILD_CFLAGS += $(cflags-y) KBUILD_CFLAGS += -mno-mmx -mno-sse KBUILD_CFLAGS += -ffreestanding -- 2.28.0 ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
[PATCH v6 11/76] x86/insn: Add insn_has_rep_prefix() helper
From: Joerg Roedel
Add a function to check whether an instruction has a REP prefix.
Signed-off-by: Joerg Roedel
Reviewed-by: Masami Hiramatsu
Link: https://lore.kernel.org/r/20200724160336.5435-11-j...@8bytes.org
---
arch/x86/include/asm/insn-eval.h | 1 +
arch/x86/lib/insn-eval.c | 24
2 files changed, 25 insertions(+)
diff --git a/arch/x86/include/asm/insn-eval.h b/arch/x86/include/asm/insn-eval.h
index f748f57f1491..a0f839aa144d 100644
--- a/arch/x86/include/asm/insn-eval.h
+++ b/arch/x86/include/asm/insn-eval.h
@@ -15,6 +15,7 @@
#define INSN_CODE_SEG_OPND_SZ(params) (params & 0xf)
#define INSN_CODE_SEG_PARAMS(oper_sz, addr_sz) (oper_sz | (addr_sz << 4))
+bool insn_has_rep_prefix(struct insn *insn);
void __user *insn_get_addr_ref(struct insn *insn, struct pt_regs *regs);
int insn_get_modrm_rm_off(struct insn *insn, struct pt_regs *regs);
int insn_get_modrm_reg_off(struct insn *insn, struct pt_regs *regs);
diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c
index a8ac5c5e94f0..8ed9d645259c 100644
--- a/arch/x86/lib/insn-eval.c
+++ b/arch/x86/lib/insn-eval.c
@@ -53,6 +53,30 @@ static bool is_string_insn(struct insn *insn)
}
}
+/**
+ * insn_has_rep_prefix() - Determine if instruction has a REP prefix
+ * @insn: Instruction containing the prefix to inspect
+ *
+ * Returns:
+ *
+ * true if the instruction has a REP prefix, false if not.
+ */
+bool insn_has_rep_prefix(struct insn *insn)
+{
+ int i;
+
+ insn_get_prefixes(insn);
+
+ for (i = 0; i < insn->prefixes.nbytes; i++) {
+ insn_byte_t p = insn->prefixes.bytes[i];
+
+ if (p == 0xf2 || p == 0xf3)
+ return true;
+ }
+
+ return false;
+}
+
/**
* get_seg_reg_override_idx() - obtain segment register override index
* @insn: Valid instruction with segment override prefixes
--
2.28.0
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[PATCH v6 23/76] x86/boot/compressed/64: Setup GHCB Based VC Exception handler
From: Joerg Roedel
Install an exception handler for #VC exception that uses a GHCB. Also
add the infrastructure for handling different exit-codes by decoding
the instruction that caused the exception and error handling.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-23-j...@8bytes.org
---
arch/x86/Kconfig | 1 +
arch/x86/boot/compressed/Makefile | 3 +
arch/x86/boot/compressed/idt_64.c | 4 +
arch/x86/boot/compressed/idt_handlers_64.S | 3 +-
arch/x86/boot/compressed/misc.c| 7 +
arch/x86/boot/compressed/misc.h| 7 +
arch/x86/boot/compressed/sev-es.c | 111 +++
arch/x86/include/asm/sev-es.h | 39 ++
arch/x86/include/uapi/asm/svm.h| 1 +
arch/x86/kernel/sev-es-shared.c| 154 +
10 files changed, 329 insertions(+), 1 deletion(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 7101ac64bb20..8289dd44efbd 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1521,6 +1521,7 @@ config AMD_MEM_ENCRYPT
select DYNAMIC_PHYSICAL_MASK
select ARCH_USE_MEMREMAP_PROT
select ARCH_HAS_FORCE_DMA_UNENCRYPTED
+ select INSTRUCTION_DECODER
help
Say yes to enable support for the encryption of system memory.
This requires an AMD processor that supports Secure Memory
diff --git a/arch/x86/boot/compressed/Makefile
b/arch/x86/boot/compressed/Makefile
index a7b8c6e59e58..4efe53a8565c 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -45,6 +45,9 @@ KBUILD_CFLAGS += -fno-asynchronous-unwind-tables
KBUILD_CFLAGS += -D__DISABLE_EXPORTS
KBUILD_CFLAGS += -include $(srctree)/include/linux/hidden.h
+# sev-es.c inludes generated $(objtree)/arch/x86/lib/inat-tables.c
+CFLAGS_sev-es.o += -I$(objtree)/arch/x86/lib/
+
KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__
GCOV_PROFILE := n
UBSAN_SANITIZE :=n
diff --git a/arch/x86/boot/compressed/idt_64.c
b/arch/x86/boot/compressed/idt_64.c
index f3ca7324be44..804a502ee0d2 100644
--- a/arch/x86/boot/compressed/idt_64.c
+++ b/arch/x86/boot/compressed/idt_64.c
@@ -46,5 +46,9 @@ void load_stage2_idt(void)
set_idt_entry(X86_TRAP_PF, boot_page_fault);
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+ set_idt_entry(X86_TRAP_VC, boot_stage2_vc);
+#endif
+
load_boot_idt(_idt_desc);
}
diff --git a/arch/x86/boot/compressed/idt_handlers_64.S
b/arch/x86/boot/compressed/idt_handlers_64.S
index 92eb4df478a1..22890e199f5b 100644
--- a/arch/x86/boot/compressed/idt_handlers_64.S
+++ b/arch/x86/boot/compressed/idt_handlers_64.S
@@ -72,5 +72,6 @@ SYM_FUNC_END(\name)
EXCEPTION_HANDLER boot_page_fault do_boot_page_fault error_code=1
#ifdef CONFIG_AMD_MEM_ENCRYPT
-EXCEPTION_HANDLER boot_stage1_vc do_vc_no_ghcb error_code=1
+EXCEPTION_HANDLER boot_stage1_vc do_vc_no_ghcberror_code=1
+EXCEPTION_HANDLER boot_stage2_vc do_boot_stage2_vcerror_code=1
#endif
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index e478e40fbe5a..267e7f93050e 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -442,6 +442,13 @@ asmlinkage __visible void *extract_kernel(void *rmode,
memptr heap,
parse_elf(output);
handle_relocations(output, output_len, virt_addr);
debug_putstr("done.\nBooting the kernel.\n");
+
+ /*
+* Flush GHCB from cache and map it encrypted again when running as
+* SEV-ES guest.
+*/
+ sev_es_shutdown_ghcb();
+
return output;
}
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 01c0fb3417ca..9995c70ca813 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -115,6 +115,12 @@ static inline void console_init(void)
void set_sev_encryption_mask(void);
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+void sev_es_shutdown_ghcb(void);
+#else
+static inline void sev_es_shutdown_ghcb(void) { }
+#endif
+
/* acpi.c */
#ifdef CONFIG_ACPI
acpi_physical_address get_rsdp_addr(void);
@@ -144,5 +150,6 @@ extern struct desc_ptr boot_idt_desc;
/* IDT Entry Points */
void boot_page_fault(void);
void boot_stage1_vc(void);
+void boot_stage2_vc(void);
#endif /* BOOT_COMPRESSED_MISC_H */
diff --git a/arch/x86/boot/compressed/sev-es.c
b/arch/x86/boot/compressed/sev-es.c
index bb91cbb5920e..7e2cec170026 100644
--- a/arch/x86/boot/compressed/sev-es.c
+++ b/arch/x86/boot/compressed/sev-es.c
@@ -13,10 +13,17 @@
#include "misc.h"
#include
+#include
+#include
#include
#include
#include
+#include "error.h"
+
+struct ghcb boot_ghcb_page __aligned(PAGE_SIZE);
+struct ghcb *boot_ghcb;
+
static inline u64 sev_es_rd_ghcb_msr(void)
{
unsigned long low, high;
@@ -38,8 +45,112 @@ static inline void sev_es_wr_ghcb_msr(u64 val)
"a"(low), "d" (high) : "memory");
[PATCH v6 07/76] x86/insn: Make inat-tables.c suitable for pre-decompression code
From: Joerg Roedel
The inat-tables.c file has some arrays in it that contain pointers to
other arrays. These pointers need to be relocated when the kernel
image is moved to a different location.
The pre-decompression boot-code has no support for applying ELF
relocations, so initialize these arrays at runtime in the
pre-decompression code to make sure all pointers are correctly
initialized.
Signed-off-by: Joerg Roedel
Acked-by: Masami Hiramatsu
Link: https://lore.kernel.org/r/20200724160336.5435-7-j...@8bytes.org
---
arch/x86/tools/gen-insn-attr-x86.awk | 50 +-
tools/arch/x86/tools/gen-insn-attr-x86.awk | 50 +-
2 files changed, 98 insertions(+), 2 deletions(-)
diff --git a/arch/x86/tools/gen-insn-attr-x86.awk
b/arch/x86/tools/gen-insn-attr-x86.awk
index a42015b305f4..af38469afd14 100644
--- a/arch/x86/tools/gen-insn-attr-x86.awk
+++ b/arch/x86/tools/gen-insn-attr-x86.awk
@@ -362,6 +362,9 @@ function convert_operands(count,opnd, i,j,imm,mod)
END {
if (awkchecked != "")
exit 1
+
+ print "#ifndef __BOOT_COMPRESSED\n"
+
# print escape opcode map's array
print "/* Escape opcode map array */"
print "const insn_attr_t * const inat_escape_tables[INAT_ESC_MAX + 1]" \
@@ -388,6 +391,51 @@ END {
for (j = 0; j < max_lprefix; j++)
if (atable[i,j])
print " ["i"]["j"] = "atable[i,j]","
- print "};"
+ print "};\n"
+
+ print "#else /* !__BOOT_COMPRESSED */\n"
+
+ print "/* Escape opcode map array */"
+ print "static const insn_attr_t *inat_escape_tables[INAT_ESC_MAX + 1]" \
+ "[INAT_LSTPFX_MAX + 1];"
+ print ""
+
+ print "/* Group opcode map array */"
+ print "static const insn_attr_t *inat_group_tables[INAT_GRP_MAX + 1]"\
+ "[INAT_LSTPFX_MAX + 1];"
+ print ""
+
+ print "/* AVX opcode map array */"
+ print "static const insn_attr_t *inat_avx_tables[X86_VEX_M_MAX + 1]"\
+ "[INAT_LSTPFX_MAX + 1];"
+ print ""
+
+ print "static void inat_init_tables(void)"
+ print "{"
+
+ # print escape opcode map's array
+ print "\t/* Print Escape opcode map array */"
+ for (i = 0; i < geid; i++)
+ for (j = 0; j < max_lprefix; j++)
+ if (etable[i,j])
+ print "\tinat_escape_tables["i"]["j"] =
"etable[i,j]";"
+ print ""
+
+ # print group opcode map's array
+ print "\t/* Print Group opcode map array */"
+ for (i = 0; i < ggid; i++)
+ for (j = 0; j < max_lprefix; j++)
+ if (gtable[i,j])
+ print "\tinat_group_tables["i"]["j"] =
"gtable[i,j]";"
+ print ""
+ # print AVX opcode map's array
+ print "\t/* Print AVX opcode map array */"
+ for (i = 0; i < gaid; i++)
+ for (j = 0; j < max_lprefix; j++)
+ if (atable[i,j])
+ print "\tinat_avx_tables["i"]["j"] =
"atable[i,j]";"
+
+ print "}"
+ print "#endif"
}
diff --git a/tools/arch/x86/tools/gen-insn-attr-x86.awk
b/tools/arch/x86/tools/gen-insn-attr-x86.awk
index a42015b305f4..af38469afd14 100644
--- a/tools/arch/x86/tools/gen-insn-attr-x86.awk
+++ b/tools/arch/x86/tools/gen-insn-attr-x86.awk
@@ -362,6 +362,9 @@ function convert_operands(count,opnd, i,j,imm,mod)
END {
if (awkchecked != "")
exit 1
+
+ print "#ifndef __BOOT_COMPRESSED\n"
+
# print escape opcode map's array
print "/* Escape opcode map array */"
print "const insn_attr_t * const inat_escape_tables[INAT_ESC_MAX + 1]" \
@@ -388,6 +391,51 @@ END {
for (j = 0; j < max_lprefix; j++)
if (atable[i,j])
print " ["i"]["j"] = "atable[i,j]","
- print "};"
+ print "};\n"
+
+ print "#else /* !__BOOT_COMPRESSED */\n"
+
+ print "/* Escape opcode map array */"
+ print "static const insn_attr_t *inat_escape_tables[INAT_ESC_MAX + 1]" \
+ "[INAT_LSTPFX_MAX + 1];"
+ print ""
+
+ print "/* Group opcode map array */"
+ print "static const insn_attr_t *inat_group_tables[INAT_GRP_MAX + 1]"\
+ "[INAT_LSTPFX_MAX + 1];"
+ print ""
+
+ print "/* AVX opcode map array */"
+ print "static const insn_attr_t *inat_avx_tables[X86_VEX_M_MAX + 1]"\
+ "[INAT_LSTPFX_MAX + 1];"
+ print ""
+
+ print "static void inat_init_tables(void)"
+ print "{"
+
+ # print escape opcode map's array
+ print "\t/* Print Escape opcode map array */"
+ for (i = 0; i < geid; i++)
+ for (j = 0; j < max_lprefix; j++)
+ if (etable[i,j])
+ print "\tinat_escape_tables["i"]["j"] =
"etable[i,j]";"
[PATCH v6 18/76] x86/boot/compressed/64: Change add_identity_map() to take start and end
From: Joerg Roedel
Changing the function to take start and end as parameters instead of
start and size simplifies the callers, which don't need to calculate
the size if they already have start and end.
Signed-off-by: Joerg Roedel
Reviewed-by: Kees Cook
Link: https://lore.kernel.org/r/20200724160336.5435-18-j...@8bytes.org
---
arch/x86/boot/compressed/ident_map_64.c | 15 +--
1 file changed, 5 insertions(+), 10 deletions(-)
diff --git a/arch/x86/boot/compressed/ident_map_64.c
b/arch/x86/boot/compressed/ident_map_64.c
index c63257bf8373..62e42c11a336 100644
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -89,10 +89,8 @@ static struct x86_mapping_info mapping_info;
/*
* Adds the specified range to the identity mappings.
*/
-static void add_identity_map(unsigned long start, unsigned long size)
+static void add_identity_map(unsigned long start, unsigned long end)
{
- unsigned long end = start + size;
-
/* Align boundary to 2M. */
start = round_down(start, PMD_SIZE);
end = round_up(end, PMD_SIZE);
@@ -107,8 +105,6 @@ static void add_identity_map(unsigned long start, unsigned
long size)
/* Locates and clears a region for a new top level page table. */
void initialize_identity_maps(void)
{
- unsigned long start, size;
-
/* If running as an SEV guest, the encryption mask is required. */
set_sev_encryption_mask();
@@ -155,9 +151,7 @@ void initialize_identity_maps(void)
* New page-table is set up - map the kernel image and load it
* into cr3.
*/
- start = (unsigned long)_head;
- size = _end - _head;
- add_identity_map(start, size);
+ add_identity_map((unsigned long)_head, (unsigned long)_end);
write_cr3(top_level_pgt);
}
@@ -189,7 +183,8 @@ static void do_pf_error(const char *msg, unsigned long
error_code,
void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code)
{
- unsigned long address = native_read_cr2();
+ unsigned long address = native_read_cr2() & PMD_MASK;
+ unsigned long end = address + PMD_SIZE;
/*
* Check for unexpected error codes. Unexpected are:
@@ -204,5 +199,5 @@ void do_boot_page_fault(struct pt_regs *regs, unsigned long
error_code)
* Error code is sane - now identity map the 2M region around
* the faulting address.
*/
- add_identity_map(address & PMD_MASK, PMD_SIZE);
+ add_identity_map(address, end);
}
--
2.28.0
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[PATCH v6 20/76] x86/boot/compressed/64: Call set_sev_encryption_mask earlier
From: Joerg Roedel
Call set_sev_encryption_mask() while still on the stage 1 #VC-handler,
because the stage 2 handler needs our own page-tables to be set up, to
which calling set_sev_encryption_mask() is a prerequisite.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-20-j...@8bytes.org
---
arch/x86/boot/compressed/head_64.S | 8 +++-
arch/x86/boot/compressed/ident_map_64.c | 3 ---
2 files changed, 7 insertions(+), 4 deletions(-)
diff --git a/arch/x86/boot/compressed/head_64.S
b/arch/x86/boot/compressed/head_64.S
index 013b29921836..c7fcf60cbd08 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -533,9 +533,15 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated)
rep stosq
/*
- * Load stage2 IDT and switch to our own page-table
+ * If running as an SEV guest, the encryption mask is required in the
+ * page-table setup code below. When the guest also has SEV-ES enabled
+ * set_sev_encryption_mask() will cause #VC exceptions, but the stage2
+ * handler can't map its GHCB because the page-table is not set up yet.
+ * So set up the encryption mask here while still on the stage1 #VC
+ * handler. Then load stage2 IDT and switch to our own page-table.
*/
pushq %rsi
+ callset_sev_encryption_mask
callload_stage2_idt
callinitialize_identity_maps
popq%rsi
diff --git a/arch/x86/boot/compressed/ident_map_64.c
b/arch/x86/boot/compressed/ident_map_64.c
index 62e42c11a336..b4f2a5f503cd 100644
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -105,9 +105,6 @@ static void add_identity_map(unsigned long start, unsigned
long end)
/* Locates and clears a region for a new top level page table. */
void initialize_identity_maps(void)
{
- /* If running as an SEV guest, the encryption mask is required. */
- set_sev_encryption_mask();
-
/* Exclude the encryption mask from __PHYSICAL_MASK */
physical_mask &= ~sme_me_mask;
--
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[PATCH v6 41/76] x86/sev-es: Compile early handler code into kernel image
From: Joerg Roedel
Setup sev-es.c and include the code from the
pre-decompression stage to also build it into the image of the running
kernel. Temporarily add __maybe_unused annotations to avoid build
warnings until the functions get used.
Signed-off-by: Joerg Roedel
Link: https://lore.kernel.org/r/20200724160336.5435-41-j...@8bytes.org
---
arch/x86/kernel/Makefile| 1 +
arch/x86/kernel/sev-es-shared.c | 21 ++--
arch/x86/kernel/sev-es.c| 163
3 files changed, 175 insertions(+), 10 deletions(-)
create mode 100644 arch/x86/kernel/sev-es.c
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index e77261db2391..23bc0f830f18 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -145,6 +145,7 @@ obj-$(CONFIG_UNWINDER_ORC) += unwind_orc.o
obj-$(CONFIG_UNWINDER_FRAME_POINTER) += unwind_frame.o
obj-$(CONFIG_UNWINDER_GUESS) += unwind_guess.o
+obj-$(CONFIG_AMD_MEM_ENCRYPT) += sev-es.o
###
# 64 bit specific files
ifeq ($(CONFIG_X86_64),y)
diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c
index a6b41910b8ab..18619279a46f 100644
--- a/arch/x86/kernel/sev-es-shared.c
+++ b/arch/x86/kernel/sev-es-shared.c
@@ -9,7 +9,7 @@
* and is included directly into both code-bases.
*/
-static void sev_es_terminate(unsigned int reason)
+static void __maybe_unused sev_es_terminate(unsigned int reason)
{
u64 val = GHCB_SEV_TERMINATE;
@@ -27,7 +27,7 @@ static void sev_es_terminate(unsigned int reason)
asm volatile("hlt\n" : : : "memory");
}
-static bool sev_es_negotiate_protocol(void)
+static bool __maybe_unused sev_es_negotiate_protocol(void)
{
u64 val;
@@ -46,7 +46,7 @@ static bool sev_es_negotiate_protocol(void)
return true;
}
-static void vc_ghcb_invalidate(struct ghcb *ghcb)
+static void __maybe_unused vc_ghcb_invalidate(struct ghcb *ghcb)
{
memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap));
}
@@ -58,9 +58,9 @@ static bool vc_decoding_needed(unsigned long exit_code)
exit_code <= SVM_EXIT_LAST_EXCP);
}
-static enum es_result vc_init_em_ctxt(struct es_em_ctxt *ctxt,
- struct pt_regs *regs,
- unsigned long exit_code)
+static enum es_result __maybe_unused vc_init_em_ctxt(struct es_em_ctxt *ctxt,
+struct pt_regs *regs,
+unsigned long exit_code)
{
enum es_result ret = ES_OK;
@@ -73,7 +73,7 @@ static enum es_result vc_init_em_ctxt(struct es_em_ctxt *ctxt,
return ret;
}
-static void vc_finish_insn(struct es_em_ctxt *ctxt)
+static void __maybe_unused vc_finish_insn(struct es_em_ctxt *ctxt)
{
ctxt->regs->ip += ctxt->insn.length;
}
@@ -325,7 +325,8 @@ static enum es_result vc_ioio_exitinfo(struct es_em_ctxt
*ctxt, u64 *exitinfo)
return ES_OK;
}
-static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt
*ctxt)
+static enum es_result __maybe_unused
+vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
{
struct pt_regs *regs = ctxt->regs;
u64 exit_info_1, exit_info_2;
@@ -433,8 +434,8 @@ static enum es_result vc_handle_ioio(struct ghcb *ghcb,
struct es_em_ctxt *ctxt)
return ret;
}
-static enum es_result vc_handle_cpuid(struct ghcb *ghcb,
- struct es_em_ctxt *ctxt)
+static enum es_result __maybe_unused vc_handle_cpuid(struct ghcb *ghcb,
+struct es_em_ctxt *ctxt)
{
struct pt_regs *regs = ctxt->regs;
u32 cr4 = native_read_cr4();
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
new file mode 100644
index ..0b698b653c0b
--- /dev/null
+++ b/arch/x86/kernel/sev-es.c
@@ -0,0 +1,163 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AMD Memory Encryption Support
+ *
+ * Copyright (C) 2019 SUSE
+ *
+ * Author: Joerg Roedel
+ */
+
+#include
+#include
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+static inline u64 sev_es_rd_ghcb_msr(void)
+{
+ return native_read_msr(MSR_AMD64_SEV_ES_GHCB);
+}
+
+static inline void sev_es_wr_ghcb_msr(u64 val)
+{
+ u32 low, high;
+
+ low = (u32)(val);
+ high = (u32)(val >> 32);
+
+ native_write_msr(MSR_AMD64_SEV_ES_GHCB, low, high);
+}
+
+static int vc_fetch_insn_kernel(struct es_em_ctxt *ctxt,
+ unsigned char *buffer)
+{
+ return copy_from_kernel_nofault(buffer, (unsigned char
*)ctxt->regs->ip, MAX_INSN_SIZE);
+}
+
+static enum es_result vc_decode_insn(struct es_em_ctxt *ctxt)
+{
+ char buffer[MAX_INSN_SIZE];
+ enum es_result ret;
+ int res;
+
+ res = vc_fetch_insn_kernel(ctxt, buffer);
+ if (unlikely(res == -EFAULT)) {
+
[PATCH AUTOSEL 5.8 06/63] drm/virtio: fix memory leak in virtio_gpu_cleanup_object()
From: Xin He [ Upstream commit 836b194d65782aaec4485a07d2aab52d3f698505 ] Before setting shmem->pages to NULL, kfree() should be called. Signed-off-by: Xin He Reviewed-by: Qi Liu Link: http://patchwork.freedesktop.org/patch/msgid/20200722051851.72662-1-hexin...@bytedance.com Signed-off-by: Gerd Hoffmann Signed-off-by: Sasha Levin --- drivers/gpu/drm/virtio/virtgpu_object.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c b/drivers/gpu/drm/virtio/virtgpu_object.c index 6ccbd01cd888c..703b5cd517519 100644 --- a/drivers/gpu/drm/virtio/virtgpu_object.c +++ b/drivers/gpu/drm/virtio/virtgpu_object.c @@ -79,6 +79,7 @@ void virtio_gpu_cleanup_object(struct virtio_gpu_object *bo) } sg_free_table(shmem->pages); + kfree(shmem->pages); shmem->pages = NULL; drm_gem_shmem_unpin(>base.base); } -- 2.25.1 ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
[PATCH AUTOSEL 5.7 05/54] drm/virtio: fix memory leak in virtio_gpu_cleanup_object()
From: Xin He [ Upstream commit 836b194d65782aaec4485a07d2aab52d3f698505 ] Before setting shmem->pages to NULL, kfree() should be called. Signed-off-by: Xin He Reviewed-by: Qi Liu Link: http://patchwork.freedesktop.org/patch/msgid/20200722051851.72662-1-hexin...@bytedance.com Signed-off-by: Gerd Hoffmann Signed-off-by: Sasha Levin --- drivers/gpu/drm/virtio/virtgpu_object.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c b/drivers/gpu/drm/virtio/virtgpu_object.c index d9039bb7c5e37..1e65c5ac573b1 100644 --- a/drivers/gpu/drm/virtio/virtgpu_object.c +++ b/drivers/gpu/drm/virtio/virtgpu_object.c @@ -79,6 +79,7 @@ void virtio_gpu_cleanup_object(struct virtio_gpu_object *bo) } sg_free_table(shmem->pages); + kfree(shmem->pages); shmem->pages = NULL; drm_gem_shmem_unpin(>base.base); } -- 2.25.1 ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
Re: Is: virtio_gpu_object_shmem_init issues? Was:Re: upstream boot error: general protection fault in swiotlb_map
On Mon, Aug 24, 2020 at 11:06:51AM -0400, Konrad Rzeszutek Wilk wrote: > So it fails at > > 683 dev_WARN_ONCE(dev, 1, > > 684 "swiotlb addr %pad+%zu overflow (mask %llx, bus > limit %llx).\n", > 685 _addr, size, *dev->dma_mask, > dev->bus_dma_limit); > > > which makes no sense to me as `dev` surely exists. I can see in the console > log: > > virtio-pci :00:01.0: vgaarb: deactivate vga console > > So what gives? Well, look at the if around the WARN_ON - dma_capable failed on the swiotlb buffer. This means the virtio drm thingy has a dma mask (either the actual one set by the driver, or bus_dma_mask), which isn't enough to address the swiotlb buffer. ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
Is: virtio_gpu_object_shmem_init issues? Was:Re: upstream boot error: general protection fault in swiotlb_map
On Thu, Aug 06, 2020 at 03:46:23AM -0700, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit:47ec5303 Merge git://git.kernel.org/pub/scm/linux/kernel/g.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=16fe1dea90 > kernel config: https://syzkaller.appspot.com/x/.config?x=7c06047f622c5724 > dashboard link: https://syzkaller.appspot.com/bug?extid=3f86afd0b1e4bf1cb64c > compiler: gcc (GCC) 10.1.0-syz 20200507 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+3f86afd0b1e4bf1cb...@syzkaller.appspotmail.com > > ceph: loaded (mds proto 32) > NET: Registered protocol family 38 > async_tx: api initialized (async) > Key type asymmetric registered > Asymmetric key parser 'x509' registered > Asymmetric key parser 'pkcs8' registered > Key type pkcs7_test registered > Asymmetric key parser 'tpm_parser' registered > Block layer SCSI generic (bsg) driver version 0.4 loaded (major 243) > io scheduler mq-deadline registered > io scheduler kyber registered > io scheduler bfq registered > hgafb: HGA card not detected. > hgafb: probe of hgafb.0 failed with error -22 > usbcore: registered new interface driver udlfb > uvesafb: failed to execute /sbin/v86d > uvesafb: make sure that the v86d helper is installed and executable > uvesafb: Getting VBE info block failed (eax=0x4f00, err=-2) > uvesafb: vbe_init() failed with -22 > uvesafb: probe of uvesafb.0 failed with error -22 > vga16fb: mapped to 0x8aac772d > Console: switching to colour frame buffer device 80x30 > fb0: VGA16 VGA frame buffer device > input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input0 > ACPI: Power Button [PWRF] > ioatdma: Intel(R) QuickData Technology Driver 5.00 > PCI Interrupt Link [GSIF] enabled at IRQ 21 > PCI Interrupt Link [GSIG] enabled at IRQ 22 > PCI Interrupt Link [GSIH] enabled at IRQ 23 > N_HDLC line discipline registered with maxframe=4096 > Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled > 00:05: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A > Cyclades driver 2.6 > Initializing Nozomi driver 2.1d > RocketPort device driver module, version 2.09, 12-June-2003 > No rocketport ports found; unloading driver > Non-volatile memory driver v1.3 > Linux agpgart interface v0.103 > [drm] Initialized vgem 1.0.0 20120112 for vgem on minor 0 > [drm] Initialized vkms 1.0.0 20180514 for vkms on minor 1 > usbcore: registered new interface driver udl > [drm] pci: virtio-vga detected at :00:01.0 > fb0: switching to virtiodrmfb from VGA16 VGA > Console: switching to colour VGA+ 80x25 > virtio-pci :00:01.0: vgaarb: deactivate vga console > Console: switching to colour dummy device 80x25 > [drm] features: -virgl +edid > [drm] number of scanouts: 1 > [drm] number of cap sets: 0 > [drm] Initialized virtio_gpu 0.1.0 0 for virtio0 on minor 2 > general protection fault, probably for non-canonical address > 0xdc00: [#1] PREEMPT SMP KASAN > KASAN: null-ptr-deref in range [0x-0x0007] > CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-syzkaller #0 > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS > rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 > RIP: 0010:swiotlb_map+0x5ac/0x700 kernel/dma/swiotlb.c:683 > Code: 28 04 00 00 48 c1 ea 03 80 3c 02 00 0f 85 4d 01 00 00 4c 8b a5 18 04 00 > 00 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 0f 85 1e > 01 00 00 48 8d 7d 50 4d 8b 24 24 48 b8 00 00 > RSP: :c934f3e0 EFLAGS: 00010246 > RAX: dc00 RBX: RCX: 8162cc1d > RDX: RSI: 8162cc98 RDI: 88802971a470 > RBP: 88802971a048 R08: 0001 R09: 8c5dba77 > R10: R11: R12: > R13: 7ac0 R14: dc00 R15: 1000 > FS: () GS:88802ce0() knlGS: > CS: 0010 DS: ES: CR0: 80050033 > CR2: CR3: 09a8d000 CR4: 00350ef0 > DR0: DR1: DR2: > DR3: DR6: fffe0ff0 DR7: 0400 > Call Trace: > dma_direct_map_page include/linux/dma-direct.h:170 [inline] > dma_direct_map_sg+0x3bb/0x670 kernel/dma/direct.c:368 > dma_map_sg_attrs+0xd0/0x160 kernel/dma/mapping.c:183 > drm_gem_shmem_get_pages_sgt drivers/gpu/drm/drm_gem_shmem_helper.c:700 > [inline] > drm_gem_shmem_get_pages_sgt+0x1fc/0x310 > drivers/gpu/drm/drm_gem_shmem_helper.c:679 > virtio_gpu_object_shmem_init drivers/gpu/drm/virtio/virtgpu_object.c:153 > [inline] > virtio_gpu_object_create+0x2fd/0xa70 > drivers/gpu/drm/virtio/virtgpu_object.c:232 > virtio_gpu_gem_create drivers/gpu/drm/virtio/virtgpu_gem.c:45 [inline] > virtio_gpu_mode_dumb_create+0x298/0x530 > drivers/gpu/drm/virtio/virtgpu_gem.c:85 >
Re: Is: virtio_gpu_object_shmem_init issues? Was:Re: upstream boot error: general protection fault in swiotlb_map
On Mon, Aug 24, 2020 at 5:07 PM Konrad Rzeszutek Wilk wrote: > > On Thu, Aug 06, 2020 at 03:46:23AM -0700, syzbot wrote: > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit:47ec5303 Merge git://git.kernel.org/pub/scm/linux/kernel/g.. > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=16fe1dea90 > > kernel config: https://syzkaller.appspot.com/x/.config?x=7c06047f622c5724 > > dashboard link: https://syzkaller.appspot.com/bug?extid=3f86afd0b1e4bf1cb64c > > compiler: gcc (GCC) 10.1.0-syz 20200507 > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > Reported-by: syzbot+3f86afd0b1e4bf1cb...@syzkaller.appspotmail.com > > > > ceph: loaded (mds proto 32) > > NET: Registered protocol family 38 > > async_tx: api initialized (async) > > Key type asymmetric registered > > Asymmetric key parser 'x509' registered > > Asymmetric key parser 'pkcs8' registered > > Key type pkcs7_test registered > > Asymmetric key parser 'tpm_parser' registered > > Block layer SCSI generic (bsg) driver version 0.4 loaded (major 243) > > io scheduler mq-deadline registered > > io scheduler kyber registered > > io scheduler bfq registered > > hgafb: HGA card not detected. > > hgafb: probe of hgafb.0 failed with error -22 > > usbcore: registered new interface driver udlfb > > uvesafb: failed to execute /sbin/v86d > > uvesafb: make sure that the v86d helper is installed and executable > > uvesafb: Getting VBE info block failed (eax=0x4f00, err=-2) > > uvesafb: vbe_init() failed with -22 > > uvesafb: probe of uvesafb.0 failed with error -22 > > vga16fb: mapped to 0x8aac772d > > Console: switching to colour frame buffer device 80x30 > > fb0: VGA16 VGA frame buffer device > > input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input0 > > ACPI: Power Button [PWRF] > > ioatdma: Intel(R) QuickData Technology Driver 5.00 > > PCI Interrupt Link [GSIF] enabled at IRQ 21 > > PCI Interrupt Link [GSIG] enabled at IRQ 22 > > PCI Interrupt Link [GSIH] enabled at IRQ 23 > > N_HDLC line discipline registered with maxframe=4096 > > Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled > > 00:05: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A > > Cyclades driver 2.6 > > Initializing Nozomi driver 2.1d > > RocketPort device driver module, version 2.09, 12-June-2003 > > No rocketport ports found; unloading driver > > Non-volatile memory driver v1.3 > > Linux agpgart interface v0.103 > > [drm] Initialized vgem 1.0.0 20120112 for vgem on minor 0 > > [drm] Initialized vkms 1.0.0 20180514 for vkms on minor 1 > > usbcore: registered new interface driver udl > > [drm] pci: virtio-vga detected at :00:01.0 > > fb0: switching to virtiodrmfb from VGA16 VGA > > Console: switching to colour VGA+ 80x25 > > virtio-pci :00:01.0: vgaarb: deactivate vga console > > Console: switching to colour dummy device 80x25 > > [drm] features: -virgl +edid > > [drm] number of scanouts: 1 > > [drm] number of cap sets: 0 > > [drm] Initialized virtio_gpu 0.1.0 0 for virtio0 on minor 2 > > general protection fault, probably for non-canonical address > > 0xdc00: [#1] PREEMPT SMP KASAN > > KASAN: null-ptr-deref in range [0x-0x0007] > > CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-syzkaller #0 > > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS > > rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 > > RIP: 0010:swiotlb_map+0x5ac/0x700 kernel/dma/swiotlb.c:683 > > Code: 28 04 00 00 48 c1 ea 03 80 3c 02 00 0f 85 4d 01 00 00 4c 8b a5 18 04 > > 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 0f > > 85 1e 01 00 00 48 8d 7d 50 4d 8b 24 24 48 b8 00 00 > > RSP: :c934f3e0 EFLAGS: 00010246 > > RAX: dc00 RBX: RCX: 8162cc1d > > RDX: RSI: 8162cc98 RDI: 88802971a470 > > RBP: 88802971a048 R08: 0001 R09: 8c5dba77 > > R10: R11: R12: > > R13: 7ac0 R14: dc00 R15: 1000 > > FS: () GS:88802ce0() knlGS: > > CS: 0010 DS: ES: CR0: 80050033 > > CR2: CR3: 09a8d000 CR4: 00350ef0 > > DR0: DR1: DR2: > > DR3: DR6: fffe0ff0 DR7: 0400 > > Call Trace: > > dma_direct_map_page include/linux/dma-direct.h:170 [inline] > > dma_direct_map_sg+0x3bb/0x670 kernel/dma/direct.c:368 > > dma_map_sg_attrs+0xd0/0x160 kernel/dma/mapping.c:183 > > drm_gem_shmem_get_pages_sgt drivers/gpu/drm/drm_gem_shmem_helper.c:700 > > [inline] > > drm_gem_shmem_get_pages_sgt+0x1fc/0x310 > > drivers/gpu/drm/drm_gem_shmem_helper.c:679 > > virtio_gpu_object_shmem_init drivers/gpu/drm/virtio/virtgpu_object.c:153 > > [inline] > >
