Re: [PATCH v4 0/8] bpf powerpc: Add BPF_PROBE_MEM support in powerpc JIT compiler
Daniel Borkmann writes: > On 9/29/21 1:18 PM, Hari Bathini wrote: >> Patch #1 & #2 are simple cleanup patches. Patch #3 refactors JIT >> compiler code with the aim to simplify adding BPF_PROBE_MEM support. >> Patch #4 introduces PPC_RAW_BRANCH() macro instead of open coding >> branch instruction. Patch #5 & #7 add BPF_PROBE_MEM support for PPC64 >> & PPC32 JIT compilers respectively. Patch #6 & #8 handle bad userspace >> pointers for PPC64 & PPC32 cases respectively. > > Michael, are you planning to pick up the series or shall we route via > bpf-next? Yeah I'll plan to take it, unless you think there is a strong reason it needs to go via the bpf tree (doesn't look like it from the diffstat). cheers
Re: [PATCH 09/10] i2c: pasemi: Add Apple platform driver
On Wed, Sep 29, 2021, at 22:33, Wolfram Sang wrote: >> drivers/i2c/busses/i2c-pasemi-apple.c | 122 ++ > > Can't we name it 'i2c-pasemi-platform.c' instead? Makes more sense to me > because the other instance is named -pci. Sure, that's more consistent. I'll change the filename for v2. Thanks, Sven
Re: Add Apple M1 support to PASemi i2c driver
Hi, On Fri, Oct 1, 2021, at 06:47, Christian Zigotzky wrote: > On 27 September 2021 at 07:39 am, Sven Peter wrote: > > Hi Christian, > > > > Thanks already for volunteering to test this! > > > Hello Sven, > > Damian (Hypex) has successfully tested the RC3 of kernel 5.15 with your > modified i2c driver on his Nemo board yesterday. [1] Thanks a lot, that's great to hear! If he wants to I can credit him with a Tested-by tag in the commit message, see e.g. https://www.kernel.org/doc/html/latest/process/submitting-patches.html#using-reported-by-tested-by-reviewed-by-suggested-by-and-fixes. Best, Sven
Re: [PATCH v4 07/11] mm: kasan: Use is_kernel() helper
On Thu, Sep 30, 2021 at 9:09 AM Kefeng Wang wrote:
>
> Directly use is_kernel() helper in kernel_or_module_addr().
>
> Cc: Andrey Ryabinin
> Cc: Alexander Potapenko
> Cc: Andrey Konovalov
> Cc: Dmitry Vyukov
> Signed-off-by: Kefeng Wang
> ---
> mm/kasan/report.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/kasan/report.c b/mm/kasan/report.c
> index 3239fd8f8747..1c955e1c98d5 100644
> --- a/mm/kasan/report.c
> +++ b/mm/kasan/report.c
> @@ -226,7 +226,7 @@ static void describe_object(struct kmem_cache *cache,
> void *object,
>
> static inline bool kernel_or_module_addr(const void *addr)
> {
> - if (addr >= (void *)_stext && addr < (void *)_end)
> + if (is_kernel((unsigned long)addr))
> return true;
> if (is_module_address((unsigned long)addr))
> return true;
> --
> 2.26.2
>
Reviewed-by: Andrey Konovalov
Re: Add Apple M1 support to PASemi i2c driver
On 03 October 2021 at 04:36 pm, Sven Peter wrote: > Hi, > > > On Fri, Oct 1, 2021, at 06:47, Christian Zigotzky wrote: >> On 27 September 2021 at 07:39 am, Sven Peter wrote: >> > Hi Christian, >> > >> > Thanks already for volunteering to test this! >> > >> Hello Sven, >> >> Damian (Hypex) has successfully tested the RC3 of kernel 5.15 with your >> modified i2c driver on his Nemo board yesterday. [1] > > Thanks a lot, that's great to hear! > If he wants to I can credit him with a Tested-by tag in the commit message, > see e.g. https://www.kernel.org/doc/html/latest/process/submitting-patches.html#using-reported-by-tested-by-reviewed-by-suggested-by-and-fixes. > > > Best, > > > Sven Hello Sven, We are still testing your i2c modifications. [1] Please wait a litte bit till we finished our tests. @Darren Could you also please check Sven's i2c modifications? He has also modified your source code a little bit. [2] @Olof Are these i2c modifications OK? Do these work on your P.A. Semi board? Thanks, Christian [1] https://forum.hyperion-entertainment.com/viewtopic.php?p=54138#p54138 [2] https://lists.ozlabs.org/pipermail/linuxppc-dev/2017-January/153195.html
Re: [PATCH 6/9] powerpc/bpf: Fix BPF_SUB when imm == 0x80000000
Le 01/10/2021 à 23:14, Naveen N. Rao a écrit :
We aren't handling subtraction involving an immediate value of
0x8000 properly. Fix the same.
Fixes: 156d0e290e969c ("powerpc/ebpf/jit: Implement JIT compiler for extended
BPF")
Signed-off-by: Naveen N. Rao
---
arch/powerpc/net/bpf_jit_comp64.c | 16
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/net/bpf_jit_comp64.c
b/arch/powerpc/net/bpf_jit_comp64.c
index ffb7a2877a8469..4641a50e82d50d 100644
--- a/arch/powerpc/net/bpf_jit_comp64.c
+++ b/arch/powerpc/net/bpf_jit_comp64.c
@@ -333,15 +333,15 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
struct codegen_context *
case BPF_ALU | BPF_SUB | BPF_K: /* (u32) dst -= (u32) imm */
case BPF_ALU64 | BPF_ADD | BPF_K: /* dst += imm */
case BPF_ALU64 | BPF_SUB | BPF_K: /* dst -= imm */
- if (BPF_OP(code) == BPF_SUB)
- imm = -imm;
- if (imm) {
- if (imm >= -32768 && imm < 32768)
- EMIT(PPC_RAW_ADDI(dst_reg, dst_reg,
IMM_L(imm)));
- else {
- PPC_LI32(b2p[TMP_REG_1], imm);
+ if (imm > -32768 && imm < 32768) {
+ EMIT(PPC_RAW_ADDI(dst_reg, dst_reg,
+ BPF_OP(code) == BPF_SUB ? IMM_L(-imm) :
IMM_L(imm)));
+ } else {
+ PPC_LI32(b2p[TMP_REG_1], imm);
+ if (BPF_OP(code) == BPF_SUB)
+ EMIT(PPC_RAW_SUB(dst_reg, dst_reg,
b2p[TMP_REG_1]));
+ else
EMIT(PPC_RAW_ADD(dst_reg, dst_reg,
b2p[TMP_REG_1]));
- }
}
goto bpf_alu32_trunc;
There is now so few code common to both BPF_ADD and BPF_SUB that you
should make them different cases.
While at it, why not also use ADDIS if imm is 32 bits ? That would be an
ADDIS/ADDI instead of LIS/ORI/ADD
case BPF_ALU | BPF_MUL | BPF_X: /* (u32) dst *= (u32) src */
Re: [PATCH 4/9] powerpc/bpf: Handle large branch ranges with BPF_EXIT
Le 01/10/2021 à 23:14, Naveen N. Rao a écrit :
In some scenarios, it is possible that the program epilogue is outside
the branch range for a BPF_EXIT instruction. Instead of rejecting such
programs, emit an indirect branch. We track the size of the bpf program
emitted after the initial run and do a second pass since BPF_EXIT can
end up emitting different number of instructions depending on the
program size.
Suggested-by: Jordan Niethe
Signed-off-by: Naveen N. Rao
---
arch/powerpc/net/bpf_jit.h| 3 +++
arch/powerpc/net/bpf_jit_comp.c | 22 +-
arch/powerpc/net/bpf_jit_comp32.c | 2 +-
arch/powerpc/net/bpf_jit_comp64.c | 2 +-
4 files changed, 26 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
index 89bd744c2bffd4..4023de1698b9f5 100644
--- a/arch/powerpc/net/bpf_jit.h
+++ b/arch/powerpc/net/bpf_jit.h
@@ -126,6 +126,7 @@
#define SEEN_FUNC 0x2000 /* might call external helpers */
#define SEEN_TAILCALL 0x4000 /* uses tail calls */
+#define SEEN_BIG_PROG 0x8000 /* large prog, >32MB */
#define SEEN_VREG_MASK 0x1ff8 /* Volatile registers r3-r12 */
#define SEEN_NVREG_MASK 0x0003 /* Non volatile registers r14-r31 */
@@ -179,6 +180,8 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
struct codegen_context *
void bpf_jit_build_prologue(u32 *image, struct codegen_context *ctx);
void bpf_jit_build_epilogue(u32 *image, struct codegen_context *ctx);
void bpf_jit_realloc_regs(struct codegen_context *ctx);
+int bpf_jit_emit_exit_insn(u32 *image, struct codegen_context *ctx,
+ int tmp_reg, unsigned long exit_addr);
#endif
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index fcbf7a917c566e..3204872fbf2738 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -72,6 +72,21 @@ static int bpf_jit_fixup_subprog_calls(struct bpf_prog *fp,
u32 *image,
return 0;
}
+int bpf_jit_emit_exit_insn(u32 *image, struct codegen_context *ctx,
+ int tmp_reg, unsigned long exit_addr)
+{
+ if (!(ctx->seen & SEEN_BIG_PROG) &&
is_offset_in_branch_range(exit_addr)) {
+ PPC_JMP(exit_addr);
+ } else {
+ ctx->seen |= SEEN_BIG_PROG;
+ PPC_FUNC_ADDR(tmp_reg, (unsigned long)image + exit_addr);
+ EMIT(PPC_RAW_MTCTR(tmp_reg));
+ EMIT(PPC_RAW_BCTR());
+ }
+
+ return 0;
+}
+
struct powerpc64_jit_data {
struct bpf_binary_header *header;
u32 *addrs;
@@ -155,12 +170,17 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
goto out_addrs;
}
+ if (!is_offset_in_branch_range((long)cgctx.idx * 4))
+ cgctx.seen |= SEEN_BIG_PROG;
+
/*
* If we have seen a tail call, we need a second pass.
* This is because bpf_jit_emit_common_epilogue() is called
* from bpf_jit_emit_tail_call() with a not yet stable ctx->seen.
+* We also need a second pass if we ended up with too large
+* a program so as to fix branches.
*/
- if (cgctx.seen & SEEN_TAILCALL) {
+ if (cgctx.seen & (SEEN_TAILCALL | SEEN_BIG_PROG)) {
cgctx.idx = 0;
if (bpf_jit_build_body(fp, 0, , addrs, false)) {
fp = org_fp;
diff --git a/arch/powerpc/net/bpf_jit_comp32.c
b/arch/powerpc/net/bpf_jit_comp32.c
index a74d52204f8da2..d2a67574a23066 100644
--- a/arch/powerpc/net/bpf_jit_comp32.c
+++ b/arch/powerpc/net/bpf_jit_comp32.c
@@ -852,7 +852,7 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
struct codegen_context *
* we'll just fall through to the epilogue.
*/
if (i != flen - 1)
- PPC_JMP(exit_addr);
+ bpf_jit_emit_exit_insn(image, ctx, tmp_reg,
exit_addr);
On ppc32, if you use tmp_reg you must flag it. But I think you could use
r0 instead.
/* else fall through to the epilogue */
break;
diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
index f06c62089b1457..3351a866ef6207 100644
--- a/arch/powerpc/net/bpf_jit_comp64.c
+++ b/arch/powerpc/net/bpf_jit_comp64.c
@@ -761,7 +761,7 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
struct codegen_context *
* we'll just fall through to the epilogue.
*/
if (i != flen - 1)
- PPC_JMP(exit_addr);
+ bpf_jit_emit_exit_insn(image, ctx,
b2p[TMP_REG_1], exit_addr);
/* else fall through to the epilogue */
break;
Re: [PATCH 3/9] powerpc/bpf: Remove unused SEEN_STACK
Le 01/10/2021 à 23:14, Naveen N. Rao a écrit : From: Ravi Bangoria SEEN_STACK is unused on PowerPC. Remove it. Also, have SEEN_TAILCALL use 0x4000. Why change SEEN_TAILCALL ? Would it be a problem to leave it as is ? Signed-off-by: Ravi Bangoria Reviewed-by: Christophe Leroy --- arch/powerpc/net/bpf_jit.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h index 7e9b978b768ed9..89bd744c2bffd4 100644 --- a/arch/powerpc/net/bpf_jit.h +++ b/arch/powerpc/net/bpf_jit.h @@ -125,8 +125,7 @@ #define COND_LE (CR0_GT | COND_CMP_FALSE) #define SEEN_FUNC 0x2000 /* might call external helpers */ -#define SEEN_STACK 0x4000 /* uses BPF stack */ -#define SEEN_TAILCALL 0x8000 /* uses tail calls */ +#define SEEN_TAILCALL 0x4000 /* uses tail calls */ #define SEEN_VREG_MASK 0x1ff8 /* Volatile registers r3-r12 */ #define SEEN_NVREG_MASK 0x0003 /* Non volatile registers r14-r31 */
Re: [PATCH 1/9] powerpc/lib: Add helper to check if offset is within conditional branch range
Le 01/10/2021 à 23:14, Naveen N. Rao a écrit :
Add a helper to check if a given offset is within the branch range for a
powerpc conditional branch instruction, and update some sites to use the
new helper.
Signed-off-by: Naveen N. Rao
---
arch/powerpc/include/asm/code-patching.h | 1 +
arch/powerpc/lib/code-patching.c | 7 ++-
arch/powerpc/net/bpf_jit.h | 7 +--
3 files changed, 8 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/include/asm/code-patching.h
b/arch/powerpc/include/asm/code-patching.h
index a95f63788c6b14..4ba834599c4d4c 100644
--- a/arch/powerpc/include/asm/code-patching.h
+++ b/arch/powerpc/include/asm/code-patching.h
@@ -23,6 +23,7 @@
#define BRANCH_ABSOLUTE 0x2
bool is_offset_in_branch_range(long offset);
+bool is_offset_in_cond_branch_range(long offset);
int create_branch(struct ppc_inst *instr, const u32 *addr,
unsigned long target, int flags);
int create_cond_branch(struct ppc_inst *instr, const u32 *addr,
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index f9a3019e37b43c..e2342b9a1ab9c9 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -228,6 +228,11 @@ bool is_offset_in_branch_range(long offset)
return (offset >= -0x200 && offset <= 0x1fc && !(offset & 0x3));
}
+bool is_offset_in_cond_branch_range(long offset)
+{
+ return offset >= -0x8000 && offset <= 0x7FFF && !(offset & 0x3);
+}
Would be better without capital letters in numbers, in extenso 0x7fff
instead of 0x7FFF
+
/*
* Helper to check if a given instruction is a conditional branch
* Derived from the conditional checks in analyse_instr()
@@ -280,7 +285,7 @@ int create_cond_branch(struct ppc_inst *instr, const u32
*addr,
offset = offset - (unsigned long)addr;
/* Check we can represent the target in the instruction format */
- if (offset < -0x8000 || offset > 0x7FFF || offset & 0x3)
+ if (!is_offset_in_cond_branch_range(offset))
return 1;
/* Mask out the flags and target, so they don't step on each other. */
diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
index 99fad093f43ec1..935ea95b66359e 100644
--- a/arch/powerpc/net/bpf_jit.h
+++ b/arch/powerpc/net/bpf_jit.h
@@ -78,11 +78,6 @@
#define PPC_FUNC_ADDR(d,i) do { PPC_LI32(d, i); } while(0)
#endif
-static inline bool is_nearbranch(int offset)
-{
- return (offset < 32768) && (offset >= -32768);
-}
-
/*
* The fly in the ointment of code size changing from pass to pass is
* avoided by padding the short branch case with a NOP.If code size
differs
@@ -91,7 +86,7 @@ static inline bool is_nearbranch(int offset)
* state.
*/
#define PPC_BCC(cond, dest) do { \
- if (is_nearbranch((dest) - (ctx->idx * 4))) {
\
+ if (is_offset_in_cond_branch_range((long)(dest) - (ctx->idx *
4))) { \
PPC_BCC_SHORT(cond, dest);\
EMIT(PPC_RAW_NOP()); \
} else { \
Re: [PATCH 2/9] powerpc/bpf: Validate branch ranges
Le 01/10/2021 à 23:14, Naveen N. Rao a écrit :
Add checks to ensure that we never emit branch instructions with
truncated branch offsets.
Suggested-by: Michael Ellerman
Signed-off-by: Naveen N. Rao
---
arch/powerpc/net/bpf_jit.h| 26 --
arch/powerpc/net/bpf_jit_comp.c | 6 +-
arch/powerpc/net/bpf_jit_comp32.c | 8 ++--
arch/powerpc/net/bpf_jit_comp64.c | 8 ++--
4 files changed, 37 insertions(+), 11 deletions(-)
diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
index 935ea95b66359e..7e9b978b768ed9 100644
--- a/arch/powerpc/net/bpf_jit.h
+++ b/arch/powerpc/net/bpf_jit.h
@@ -24,16 +24,30 @@
#define EMIT(instr) PLANT_INSTR(image, ctx->idx, instr)
/* Long jump; (unconditional 'branch') */
-#define PPC_JMP(dest) EMIT(PPC_INST_BRANCH |\
-(((dest) - (ctx->idx * 4)) & 0x03fc))
+#define PPC_JMP(dest)\
+ do { \
+ long offset = (long)(dest) - (ctx->idx * 4); \
+ if (!is_offset_in_branch_range(offset)) { \
+ pr_err_ratelimited("Branch offset 0x%lx (@%u) out of
range\n", offset, ctx->idx); \
Does it really deserves a KERN_ERR ?
Isn't that something that can trigger with a userland request ?
+ return -ERANGE; \
+ } \
+ EMIT(PPC_INST_BRANCH | (offset & 0x03fc));
\
+ } while (0)
+
/* blr; (unconditional 'branch' with link) to absolute address */
#define PPC_BL_ABS(dest) EMIT(PPC_INST_BL |\
(((dest) - (unsigned long)(image + ctx->idx))
& 0x03fc))
/* "cond" here covers BO:BI fields. */
-#define PPC_BCC_SHORT(cond, dest) EMIT(PPC_INST_BRANCH_COND | \
-(((cond) & 0x3ff) << 16) |
\
-(((dest) - (ctx->idx * 4)) & \
- 0xfffc))
+#define PPC_BCC_SHORT(cond, dest)\
+ do { \
+ long offset = (long)(dest) - (ctx->idx * 4); \
+ if (!is_offset_in_cond_branch_range(offset)) {\
+ pr_err_ratelimited("Conditional branch offset 0x%lx (@%u) out
of range\n", offset, ctx->idx); \
Same
+ return -ERANGE; \
+ } \
+ EMIT(PPC_INST_BRANCH_COND | (((cond) & 0x3ff) << 16) | (offset
& 0xfffc));\
+ } while (0)
+
/* Sign-extended 32-bit immediate load */
#define PPC_LI32(d, i)do {
\
if ((int)(uintptr_t)(i) >= -32768 && \
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 53aefee3fe70be..fcbf7a917c566e 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -210,7 +210,11 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
/* Now build the prologue, body code & epilogue for real. */
cgctx.idx = 0;
bpf_jit_build_prologue(code_base, );
- bpf_jit_build_body(fp, code_base, , addrs, extra_pass);
+ if (bpf_jit_build_body(fp, code_base, , addrs,
extra_pass)) {
+ bpf_jit_binary_free(bpf_hdr);
+ fp = org_fp;
+ goto out_addrs;
+ }
bpf_jit_build_epilogue(code_base, );
if (bpf_jit_enable > 1)
diff --git a/arch/powerpc/net/bpf_jit_comp32.c
b/arch/powerpc/net/bpf_jit_comp32.c
index beb12cbc8c2994..a74d52204f8da2 100644
--- a/arch/powerpc/net/bpf_jit_comp32.c
+++ b/arch/powerpc/net/bpf_jit_comp32.c
@@ -200,7 +200,7 @@ void bpf_jit_emit_func_call_rel(u32 *image, struct
codegen_context *ctx, u64 fun
}
}
-static void bpf_jit_emit_tail_call(u32 *image, struct codegen_context *ctx, u32 out)
+static int bpf_jit_emit_tail_call(u32 *image, struct codegen_context *ctx, u32
out)
{
/*
* By now, the eBPF program has already setup parameters in r3-r6
@@ -261,7 +261,9 @@ static void bpf_jit_emit_tail_call(u32 *image, struct
codegen_context *ctx, u32
bpf_jit_emit_common_epilogue(image, ctx);
EMIT(PPC_RAW_BCTR());
+
/* out: */
+ return 0;
}
/* Assemble
