+ kmemleak-add-checksum-to-backtrace-report.patch added to mm-unstable branch

+ kmemleak-add-checksum-to-backtrace-report.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: kmemleak: add checksum to backtrace report
has been added to the -mm mm-unstable branch.  Its filename is
     kmemleak-add-checksum-to-backtrace-report.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kmemleak-add-checksum-to-backtrace-report.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Jim Cromie <jim.cromie@gmail.com>
Subject: kmemleak: add checksum to backtrace report
Date: Thu, 16 Nov 2023 15:43:18 -0700

Change /sys/kernel/debug/kmemleak report format slightly, adding
"(extra info)" to the backtrace header:

from: "  backtrace:"
to:   "  backtrace (crc <cksum>):"

The <cksum> allows a user to see recurring backtraces without
detailed/careful reading of multiline stacks.  So after cycling
kmemleak-test a few times, I know some leaks are repeating.

  bash-5.2# grep backtrace /sys/kernel/debug/kmemleak | wc
     62     186    1792
  bash-5.2# grep backtrace /sys/kernel/debug/kmemleak | sort -u | wc
     37     111    1067

syzkaller parses kmemleak for "unreferenced object" only, so is
unaffected by this change.  Other github repos are moribund.

Link: https://lkml.kernel.org/r/20231116224318.124209-3-jim.cromie@gmail.com
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/kmemleak.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/kmemleak.c~kmemleak-add-checksum-to-backtrace-report
+++ a/mm/kmemleak.c
@@ -362,7 +362,7 @@ static void print_unreferenced(struct se
 	warn_or_seq_printf(seq, "  comm \"%s\", pid %d, jiffies %lu\n",
 			   object->comm, object->pid, object->jiffies);
 	hex_dump_object(seq, object);
-	warn_or_seq_printf(seq, "  backtrace:\n");
+	warn_or_seq_printf(seq, "  backtrace (crc %x):\n", object->checksum);
 
 	for (i = 0; i < nr_entries; i++) {
 		void *ptr = (void *)entries[i];
_

Patches currently in -mm which might be from jim.cromie@gmail.com are

kmemleak-drop-age-increasing-from-leak-record.patch
kmemleak-add-checksum-to-backtrace-report.patch