[syzbot] [gfs2?] WARNING in gfs2_put_super (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 66ba480978ce Add linux-next specific files for 20260325
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1056d752580000
kernel config: https://syzkaller.appspot.com/x/.config?x=5782739fc9debc4
dashboard link: https://syzkaller.appspot.com/bug?extid=c5e536ca62b3854e739b
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/771dba450de5/disk-66ba4809.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d25fd753a911/vmlinux-66ba4809.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a61db95be18c/bzImage-66ba4809.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c5e536...@syzkaller.appspotmail.com

BUG gfs2-bufdata/syz:syz (Not tainted): Objects remaining on __kmem_cache_shutdown()
-----------------------------------------------------------------------------
Object 0xffff8880246d8460 @offset=1120
Slab 0xffffea000091b600 objects=36 used=1 fp=0xffff8880246d8000 flags=0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
Disabling lock debugging due to kernel taint
------------[ cut here ]------------
1
WARNING: mm/slub.c:1231 at __slab_err+0x15/0x20 mm/slub.c:1231, CPU#1: syz-executor/5843
Modules linked in:
CPU: 1 UID: 0 PID: 5843 Comm: syz-executor Tainted: G B syzkaller #0 PREEMPT(full)
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:__slab_err+0x15/0x20 mm/slub.c:1231
Code: 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 e8 5b 01 00 00 bf 05 00 00 00 be 01 00 00 00 e8 cc 99 5e 00 90 <0f> 0b 90 e9 53 75 8b 0a cc 66 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90003f17bf8 EFLAGS: 00010093
RAX: ffffffff8186d52a RBX: ffffc90003f17c20 RCX: ffff888076570000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff9323f0a7 R09: 1ffffffff2647e14
R10: dffffc0000000000 R11: fffffbfff2647e15 R12: ffff88802b0c81c8
R13: ffffea000091b600 R14: ffffea0000a42850 R15: ffff88802b0c8180
FS: 0000555577af5500(0000) GS:ffff88812554a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000a49030 CR3: 00000000678d8000 CR4: 00000000003526f0
Call Trace:
<TASK>
free_partial mm/slub.c:7940 [inline]
__kmem_cache_shutdown+0x13b/0x2a0 mm/slub.c:7983
kmem_cache_destroy+0x8e/0x170 mm/slab_common.c:569
gfs2_put_super+0x83f/0x890 fs/gfs2/super.c:642
generic_shutdown_super+0x13d/0x2d0 fs/super.c:646
kill_block_super+0x44/0x90 fs/super.c:1725
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:269 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd5f7b9d9d7
Code: a2 c7 05 1c fd 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffde2411ff8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fd5f7c32050 RCX: 00007fd5f7b9d9d7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffde24120b0
RBP: 00007ffde24120b0 R08: 00007ffde24130b0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffde2413140
R13: 00007fd5f7c32050 R14: 0000000000049ffd R15: 00007ffde2413180
</TASK>


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