diff options
| author | Masami Hiramatsu <mhiramat@kernel.org> | 2021-10-21 02:55:00 +0200 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2021-10-22 18:16:53 +0200 |
| commit | fc6d647638a8412800dfd10ad687709cb4aee373 (patch) | |
| tree | 0da06b9037ca670a5a513cbe50bb47676b381022 /arch | |
| parent | arm64: kprobes: Record frame pointer with kretprobe instance (diff) | |
| download | linux-fc6d647638a8412800dfd10ad687709cb4aee373.tar.xz linux-fc6d647638a8412800dfd10ad687709cb4aee373.zip | |
arm64: kprobes: Make a frame pointer on __kretprobe_trampoline
Make a frame pointer (make the x29 register points the
address of pt_regs->regs[29]) on __kretprobe_trampoline.
This frame pointer will be used by the stacktracer when it is
called from the kretprobe handlers. In this case, the stack
tracer will unwind stack to trampoline_probe_handler() and
find the next frame pointer in the stack frame of the
__kretprobe_trampoline().
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/kernel/probes/kprobes_trampoline.S | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/arm64/kernel/probes/kprobes_trampoline.S b/arch/arm64/kernel/probes/kprobes_trampoline.S index 520ee8711db1..9a6499bed58b 100644 --- a/arch/arm64/kernel/probes/kprobes_trampoline.S +++ b/arch/arm64/kernel/probes/kprobes_trampoline.S @@ -66,6 +66,9 @@ SYM_CODE_START(__kretprobe_trampoline) save_all_base_regs + /* Setup a frame pointer. */ + add x29, sp, #S_FP + mov x0, sp bl trampoline_probe_handler /* @@ -74,6 +77,7 @@ SYM_CODE_START(__kretprobe_trampoline) */ mov lr, x0 + /* The frame pointer (x29) is restored with other registers. */ restore_all_base_regs add sp, sp, #PT_REGS_SIZE |