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| author | Clément Léger <cleger@rivosinc.com> | 2023-10-04 16:10:09 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-08-29 18:33:33 +0300 |
| commit | d5a9588cc389f4e2b77fa2479a8ba86192afbfee (patch) | |
| tree | 6f53ea9a943da94a01682e369bf089c64f0e482e /arch | |
| parent | 18b9264a138992910bcc4fe83ed7f80ce3bf81ee (diff) | |
| download | linux-d5a9588cc389f4e2b77fa2479a8ba86192afbfee.tar.xz | |
riscv: blacklist assembly symbols for kprobe
[ Upstream commit 5014396af9bbac0f28d9afee7eae405206d01ee7 ]
Adding kprobes on some assembly functions (mainly exception handling)
will result in crashes (either recursive trap or panic). To avoid such
errors, add ASM_NOKPROBE() macro which allow adding specific symbols
into the __kprobe_blacklist section and use to blacklist the following
symbols that showed to be problematic:
- handle_exception()
- ret_from_exception()
- handle_kernel_stack_overflow()
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Link: https://lore.kernel.org/r/20231004131009.409193-1-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/riscv/include/asm/asm.h | 10 | ||||
| -rw-r--r-- | arch/riscv/kernel/entry.S | 3 |
2 files changed, 13 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/asm.h b/arch/riscv/include/asm/asm.h index bfb4c26f113c..b5b84c6be01e 100644 --- a/arch/riscv/include/asm/asm.h +++ b/arch/riscv/include/asm/asm.h @@ -164,6 +164,16 @@ REG_L x31, PT_T6(sp) .endm +/* Annotate a function as being unsuitable for kprobes. */ +#ifdef CONFIG_KPROBES +#define ASM_NOKPROBE(name) \ + .pushsection "_kprobe_blacklist", "aw"; \ + RISCV_PTR name; \ + .popsection +#else +#define ASM_NOKPROBE(name) +#endif + #endif /* __ASSEMBLY__ */ #endif /* _ASM_RISCV_ASM_H */ diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index 278d01d2911f..ed7baf2cf7e8 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -105,6 +105,7 @@ _save_context: 1: tail do_trap_unknown SYM_CODE_END(handle_exception) +ASM_NOKPROBE(handle_exception) /* * The ret_from_exception must be called with interrupt disabled. Here is the @@ -171,6 +172,7 @@ SYM_CODE_START_NOALIGN(ret_from_exception) sret #endif SYM_CODE_END(ret_from_exception) +ASM_NOKPROBE(ret_from_exception) #ifdef CONFIG_VMAP_STACK SYM_CODE_START_LOCAL(handle_kernel_stack_overflow) @@ -206,6 +208,7 @@ SYM_CODE_START_LOCAL(handle_kernel_stack_overflow) move a0, sp tail handle_bad_stack SYM_CODE_END(handle_kernel_stack_overflow) +ASM_NOKPROBE(handle_kernel_stack_overflow) #endif SYM_CODE_START(ret_from_fork) |