From: Jiri Slaby <jslaby@suse.cz>
Date: Fri, 1 Dec 2017 08:20:00 +0100
Subject: x86/stacktrace: do now unwind after user regs
Patch-mainline: submitted on 2017/12/5
References: bnc#1058115
Josh pointed out, that there is no way a frame can be after user regs.
So remove the last unwind and the check.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
---
arch/x86/kernel/stacktrace.c | 9 ---------
1 file changed, 9 deletions(-)
--- a/arch/x86/kernel/stacktrace.c
+++ b/arch/x86/kernel/stacktrace.c
@@ -113,15 +113,6 @@ __save_stack_trace_reliable(struct stack
if (!user_mode(regs))
return -EINVAL;
- /*
- * The last frame contains the user mode syscall
- * pt_regs. Skip it and finish the unwind.
- */
- unwind_next_frame(&state);
- if (!unwind_done(&state)) {
- STACKTRACE_DUMP_ONCE(task);
- return -EINVAL;
- }
break;
}