From d81675b60d0959cfa3727f03d5b90558fb457011 Mon Sep 17 00:00:00 2001 From: Vasily Gorbik Date: Wed, 28 Apr 2021 16:29:40 +0200 Subject: s390/unwind: recover kretprobe modified return address in stacktrace Based on commit cd9bc2c92588 ("arm64: Recover kretprobe modified return address in stacktrace"). """ Since the kretprobe replaces the function return address with the __kretprobe_trampoline on the stack, stack unwinder shows it instead of the correct return address. This checks whether the next return address is the __kretprobe_trampoline(), and if so, try to find the correct return address from the kretprobe instance list. """ Original patch series: https://lore.kernel.org/all/163163030719.489837.2236069935502195491.stgit@devnote2/ Reviewed-by: Tobias Huschle Signed-off-by: Vasily Gorbik --- arch/s390/kernel/unwind_bc.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'arch/s390/kernel') diff --git a/arch/s390/kernel/unwind_bc.c b/arch/s390/kernel/unwind_bc.c index 707fd99f6734..984970389bab 100644 --- a/arch/s390/kernel/unwind_bc.c +++ b/arch/s390/kernel/unwind_bc.c @@ -103,13 +103,11 @@ bool unwind_next_frame(struct unwind_state *state) if (sp & 0x7) goto out_err; - ip = ftrace_graph_ret_addr(state->task, &state->graph_idx, ip, (void *) sp); - /* Update unwind state */ state->sp = sp; - state->ip = ip; state->regs = regs; state->reliable = reliable; + state->ip = unwind_recover_ret_addr(state, ip); return true; out_err: @@ -161,12 +159,10 @@ void __unwind_start(struct unwind_state *state, struct task_struct *task, ip = READ_ONCE_NOCHECK(sf->gprs[8]); } - ip = ftrace_graph_ret_addr(state->task, &state->graph_idx, ip, NULL); - /* Update unwind state */ state->sp = sp; - state->ip = ip; state->reliable = true; + state->ip = unwind_recover_ret_addr(state, ip); if (!first_frame) return; -- cgit v1.2.3