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 5.18-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-5.18 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e881657d8ff0377cfd861e664e7e198f7d0ca102 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 6892ca67d9c6..b6d7ece7bf51 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -93,6 +93,7 @@ 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; }