The previous change (Fixes commit) messed up the rsp register value,
which is wrong because it's already adjusted with FRAME_SIZE, we need
the original value (after UNWIND_HINT_FUNC hint).
Fixes: 20a0bc10272f ("x86/fgraph,bpf: Fix stack ORC unwind from kprobe_multi
return probe")
Signed-off-by: Jiri Olsa <[email protected]>
---
arch/x86/kernel/ftrace_64.S | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S
index a132608265f6..613be81b6e88 100644
--- a/arch/x86/kernel/ftrace_64.S
+++ b/arch/x86/kernel/ftrace_64.S
@@ -368,13 +368,15 @@ SYM_CODE_START(return_to_handler)
subq $8, %rsp
UNWIND_HINT_FUNC
+ movq %rsp, %rdi
+
/* Save ftrace_regs for function exit context */
subq $(FRAME_SIZE), %rsp
movq %rax, RAX(%rsp)
movq %rdx, RDX(%rsp)
movq %rbp, RBP(%rsp)
- movq %rsp, RSP(%rsp)
+ movq %rdi, RSP(%rsp)
movq %rsp, %rdi
call ftrace_return_to_handler
--
2.52.0
