From: Ram Pai <linux...@us.ibm.com>
Make the Enter-Secure-Mode (ESM) ultravisor call to switch the VM to secure
mode. Add "svm=" command line option to turn on switching to secure mode.
Signed-off-by: Ram Pai <linux...@us.ibm.com>
[ andmike: Generate an RTAS os-term hcall when the ESM ucall fails. ]
Signed-off-by: Michael Anderson <andm...@linux.ibm.com>
[ bauerman: Cleaned up the code a bit. ]
Signed-off-by: Thiago Jung Bauermann <bauer...@linux.ibm.com>
---
.../admin-guide/kernel-parameters.txt | 5 +
arch/powerpc/include/asm/ultravisor-api.h | 1 +
arch/powerpc/kernel/prom_init.c | 99 +++++++++++++++++++
3 files changed, 105 insertions(+)
diff --git a/Documentation/admin-guide/kernel-parameters.txt
b/Documentation/admin-guide/kernel-parameters.txt
index 7b15abf7db21..c611891b5992 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -4585,6 +4585,11 @@
/sys/power/pm_test). Only available when CONFIG_PM_DEBUG
is set. Default value is 5.
+ svm= [PPC]
+ Format: { on | off | y | n | 1 | 0 }
+ This parameter controls use of the Protected
+ Execution Facility on pSeries.
+
swapaccount=[0|1]
[KNL] Enable accounting of swap in memory resource
controller if no parameter or 1 is given or disable
diff --git a/arch/powerpc/include/asm/ultravisor-api.h
b/arch/powerpc/include/asm/ultravisor-api.h
index c8180427fa01..fe9a0d8d7673 100644
--- a/arch/powerpc/include/asm/ultravisor-api.h
+++ b/arch/powerpc/include/asm/ultravisor-api.h
@@ -19,6 +19,7 @@
/* opcodes */
#define UV_WRITE_PATE 0xF104
+#define UV_ESM 0xF110
#define UV_RETURN 0xF11C
#define UV_REGISTER_MEM_SLOT 0xF120
#define UV_UNREGISTER_MEM_SLOT 0xF124
diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index a3fb90bb5a39..6389a992451b 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -44,6 +44,7 @@
#include <asm/sections.h>
#include <asm/machdep.h>
#include <asm/asm-prototypes.h>
+#include <asm/ultravisor-api.h>
#include <linux/linux_logo.h>
@@ -175,6 +176,10 @@ static bool __prombss prom_radix_disable;
static bool __prombss prom_xive_disable;
#endif
+#ifdef CONFIG_PPC_SVM
+static bool __prombss prom_svm_enable;
+#endif
+
struct platform_support {
bool hash_mmu;
bool radix_mmu;
@@ -816,6 +821,17 @@ static void __init early_cmdline_parse(void)
prom_debug("XIVE disabled from cmdline\n");
}
#endif /* CONFIG_PPC_PSERIES */
+
+#ifdef CONFIG_PPC_SVM
+ opt = prom_strstr(prom_cmd_line, "svm=");
+ if (opt) {
+ bool val;
+
+ opt += sizeof("svm=") - 1;
+ if (!prom_strtobool(opt, &val))
+ prom_svm_enable = val;
+ }
+#endif /* CONFIG_PPC_SVM */
}
#ifdef CONFIG_PPC_PSERIES
@@ -1716,6 +1732,43 @@ static void __init prom_close_stdin(void)
}
}
+#ifdef CONFIG_PPC_SVM
+static int prom_rtas_hcall(uint64_t args)
+{
+ register uint64_t arg1 asm("r3") = H_RTAS;
+ register uint64_t arg2 asm("r4") = args;
+
+ asm volatile("sc 1\n" : "=r" (arg1) :
+ "r" (arg1),
+ "r" (arg2) :);
+ return arg1;
+}
+
+static struct rtas_args __prombss os_term_args;
+
+static void __init prom_rtas_os_term(char *str)
+{
+ phandle rtas_node;
+ __be32 val;
+ u32 token;
+
+ prom_debug("%s: start...\n", __func__);
+ rtas_node = call_prom("finddevice", 1, 1, ADDR("/rtas"));
+ prom_debug("rtas_node: %x\n", rtas_node);
+ if (!PHANDLE_VALID(rtas_node))
+ return;
+
+ val = 0;
+ prom_getprop(rtas_node, "ibm,os-term", &val, sizeof(val));
+ token = be32_to_cpu(val);
+ prom_debug("ibm,os-term: %x\n", token);
+ if (token == 0)
+ prom_panic("Could not get token for ibm,os-term\n");
+ os_term_args.token = cpu_to_be32(token);
+ prom_rtas_hcall((uint64_t)&os_term_args);
+}
+#endif /* CONFIG_PPC_SVM */
+
/*
* Allocate room for and instantiate RTAS
*/
@@ -3172,6 +3225,49 @@ static void unreloc_toc(void)
#endif
#endif
+#ifdef CONFIG_PPC_SVM
+/*
+ * Perform the Enter Secure Mode ultracall.
+ */
+static int enter_secure_mode(unsigned long kbase, unsigned long fdt)
+{
+ register uint64_t func asm("r3") = UV_ESM;
+ register uint64_t arg1 asm("r4") = (uint64_t)kbase;
+ register uint64_t arg2 asm("r5") = (uint64_t)fdt;
+
+ asm volatile("sc 2\n"
+ : "=r"(func)
+ : "0"(func), "r"(arg1), "r"(arg2)
+ :);
+
+ return (int)func;
+}
+
+/*
+ * Call the Ultravisor to transfer us to secure memory if we have an ESM blob.
+ */
+static void setup_secure_guest(unsigned long kbase, unsigned long fdt)
+{
+ int ret;
+
+ if (!prom_svm_enable)
+ return;
+
+ /* Switch to secure mode. */
+ prom_printf("Switching to secure mode.\n");
+
+ ret = enter_secure_mode(kbase, fdt);
+ if (ret != U_SUCCESS) {
+ prom_printf("Returned %d from switching to secure mode.\n",
ret);
+ prom_rtas_os_term("Switch to secure mode failed.\n");
+ }
+}
+#else
+static void setup_secure_guest(unsigned long kbase, unsigned long fdt)
+{
+}
+#endif /* CONFIG_PPC_SVM */
+
/*
* We enter here early on, when the Open Firmware prom is still
* handling exceptions and the MMU hash table for us.
@@ -3370,6 +3466,9 @@ unsigned long __init prom_init(unsigned long r3, unsigned
long r4,
unreloc_toc();
#endif
+ /* Move to secure memory if we're supposed to be secure guests. */
+ setup_secure_guest(kbase, hdr);
+
__start(hdr, kbase, 0, 0, 0, 0, 0);
return 0;
