diff options
Diffstat (limited to 'arch/arm/probes/kprobes/core.c')
| -rw-r--r-- | arch/arm/probes/kprobes/core.c | 28 |
1 files changed, 24 insertions, 4 deletions
diff --git a/arch/arm/probes/kprobes/core.c b/arch/arm/probes/kprobes/core.c index 95f23b47ba27..4848404ba51b 100644 --- a/arch/arm/probes/kprobes/core.c +++ b/arch/arm/probes/kprobes/core.c @@ -368,16 +368,36 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, /* * When a retprobed function returns, trampoline_handler() is called, * calling the kretprobe's handler. We construct a struct pt_regs to - * give a view of registers r0-r11 to the user return-handler. This is - * not a complete pt_regs structure, but that should be plenty sufficient - * for kretprobe handlers which should normally be interested in r0 only - * anyway. + * give a view of registers r0-r11, sp, lr, and pc to the user + * return-handler. This is not a complete pt_regs structure, but that + * should be enough for stacktrace from the return handler with or + * without pt_regs. */ void __naked __kprobes __kretprobe_trampoline(void) { __asm__ __volatile__ ( +#ifdef CONFIG_FRAME_POINTER + "ldr lr, =__kretprobe_trampoline \n\t" + /* __kretprobe_trampoline makes a framepointer on pt_regs. */ +#ifdef CONFIG_CC_IS_CLANG + "stmdb sp, {sp, lr, pc} \n\t" + "sub sp, sp, #12 \n\t" + /* In clang case, pt_regs->ip = lr. */ + "stmdb sp!, {r0 - r11, lr} \n\t" + /* fp points regs->r11 (fp) */ + "add fp, sp, #44 \n\t" +#else /* !CONFIG_CC_IS_CLANG */ + /* In gcc case, pt_regs->ip = fp. */ + "stmdb sp, {fp, sp, lr, pc} \n\t" "sub sp, sp, #16 \n\t" "stmdb sp!, {r0 - r11} \n\t" + /* fp points regs->r15 (pc) */ + "add fp, sp, #60 \n\t" +#endif /* CONFIG_CC_IS_CLANG */ +#else /* !CONFIG_FRAME_POINTER */ + "sub sp, sp, #16 \n\t" + "stmdb sp!, {r0 - r11} \n\t" +#endif /* CONFIG_FRAME_POINTER */ "mov r0, sp \n\t" "bl trampoline_handler \n\t" "mov lr, r0 \n\t" |