This is a note to let you know that I've just added the patch titled
ftrace/x86: Add back ftrace_expected assignment
to the 5.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ftrace-x86-add-back-ftrace_expected-assignment.patch
and it can be found in the queue-5.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 64fc62d5d534496e9c262c5f45b6053c5d019208
Author: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
Date: Tue Jul 26 10:18:51 2022 -0400
ftrace/x86: Add back ftrace_expected assignment
[ Upstream commit ac6c1b2ca77e722a1e5d651f12f437f2f237e658 ]
When a ftrace_bug happens (where ftrace fails to modify a location) it is
helpful to have what was at that location as well as what was expected to
be there.
But with the conversion to text_poke() the variable that assigns the
expected for debugging was dropped. Unfortunately, I noticed this when I
needed it. Add it back.
Link: https://lkml.kernel.org/r/20220726101851.069d2e70@xxxxxxxxxxxxxxxxxx
Cc: "x86@xxxxxxxxxx" <x86@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 768ae4406a5c ("x86/ftrace: Use text_poke()")
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 24b9fa89aa27..bd165004776d 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -91,6 +91,7 @@ static int ftrace_verify_code(unsigned long ip, const char *old_code)
/* Make sure it is what we expect it to be */
if (memcmp(cur_code, old_code, MCOUNT_INSN_SIZE) != 0) {
+ ftrace_expected = old_code;
WARN_ON(1);
return -EINVAL;
}
