The patch titled
Subject: mm: use stack_depot_early_init for kmemleak
has been added to the -mm mm-unstable branch. Its filename is
mm-use-stack_depot_early_init-for-kmemleak.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-use-stack_depot_early_init-for-kmemleak.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx>
Subject: mm: use stack_depot_early_init for kmemleak
Date: Thu, 19 Jan 2023 09:22:25 +0800
Mirsad report the below error which is caused by stack_depot_init()
failure in kvcalloc. Solve this by having stackdepot use
stack_depot_early_init().
On 1/4/23 17:08, Mirsad Goran Todorovac wrote:
I hate to bring bad news again, but there seems to be a problem with the output of /sys/kernel/debug/kmemleak:
[root@pc-mtodorov ~]# cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff951c118568b0 (size 16):
comm "kworker/u12:2", pid 56, jiffies 4294893952 (age 4356.548s)
hex dump (first 16 bytes):
6d 65 6d 73 74 69 63 6b 30 00 00 00 00 00 00 00 memstick0.......
backtrace:
[root@pc-mtodorov ~]#
Apparently, backtrace of called functions on the stack is no longer printed with the list of memory leaks.
This appeared on Lenovo desktop 10TX000VCR, with AlmaLinux 8.7 and BIOS version M22KT49A (11/10/2022)
and 6.2-rc1 and 6.2-rc2 builds.
This worked on 6.1 with the same CONFIG_KMEMLEAK=y and MGLRU enabled on a vanilla mainstream kernel
from Mr. Torvalds' tree. I don't know if this is deliberate feature for some reason or a bug.
Please find attached the config, lshw and kmemleak output.
Link: https://lore.kernel.org/all/5272a819-ef74-65ff-be61-4d2d567337de@xxxxxxxxxxxx/
Link: https://lkml.kernel.org/r/1674091345-14799-2-git-send-email-zhaoyang.huang@xxxxxxxxxx
Fixes: 56a61617dd22 ("mm: use stack_depot for recording kmemleak's backtrace")
Reported-by: Mirsad Todorovac <mirsad.todorovac@xxxxxxxxxxxx>
Suggested-by: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx>
Acked-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: ke.wang <ke.wang@xxxxxxxxxx>
Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
Cc: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/mm/Kconfig.debug~mm-use-stack_depot_early_init-for-kmemleak
+++ a/mm/Kconfig.debug
@@ -219,6 +219,7 @@ config DEBUG_KMEMLEAK
select KALLSYMS
select CRC32
select STACKDEPOT
+ select STACKDEPOT_ALWAYS_INIT if !DEBUG_KMEMLEAK_DEFAULT_OFF
help
Say Y here if you want to enable the memory leak
detector. The memory allocation/freeing is traced in a way
--- a/mm/kmemleak.c~mm-use-stack_depot_early_init-for-kmemleak
+++ a/mm/kmemleak.c
@@ -2069,8 +2069,10 @@ static int __init kmemleak_boot_config(c
return -EINVAL;
if (strcmp(str, "off") == 0)
kmemleak_disable();
- else if (strcmp(str, "on") == 0)
+ else if (strcmp(str, "on") == 0) {
kmemleak_skip_disable = 1;
+ stack_depot_want_early_init();
+ }
else
return -EINVAL;
return 0;
_
Patches currently in -mm which might be from zhaoyang.huang@xxxxxxxxxx are
mm-move-kmemleaks-kconfig-items-from-lib-to-mm.patch
mm-use-stack_depot_early_init-for-kmemleak.patch
