[v5.15] WARNING: locking bug in gfs2_quotad (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 91d48252ad4b Linux 5.15.202
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1458c1ba580000
kernel config: https://syzkaller.appspot.com/x/.config?x=353ae28c40b35af5
dashboard link: https://syzkaller.appspot.com/bug?extid=c062679d882be99eccbc
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/74e75dfcb812/disk-91d48252.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/bfa72aab00f2/vmlinux-91d48252.xz
kernel image: https://storage.googleapis.com/syzbot-assets/47ea72d1c7dc/bzImage-91d48252.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c06267...@syzkaller.appspotmail.com

------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(1)
WARNING: CPU: 1 PID: 5214 at kernel/locking/lockdep.c:201 hlock_class kernel/locking/lockdep.c:-1 [inline]
WARNING: CPU: 1 PID: 5214 at kernel/locking/lockdep.c:201 check_wait_context kernel/locking/lockdep.c:4686 [inline]
WARNING: CPU: 1 PID: 5214 at kernel/locking/lockdep.c:201 __lock_acquire+0x7dc/0x7d10 kernel/locking/lockdep.c:4962
Modules linked in:
CPU: 1 PID: 5214 Comm: gfs2_quotad Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:hlock_class kernel/locking/lockdep.c:201 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4686 [inline]
RIP: 0010:__lock_acquire+0x7dc/0x7d10 kernel/locking/lockdep.c:4962
Code: 83 3d 3f 0a 2d 0c 00 0f 85 c7 fd ff ff 48 c7 c7 20 26 2b 8a 48 c7 c6 c0 28 2b 8a e8 7e 6c 54 08 48 ba 00 00 00 00 00 fc ff df <0f> 0b e9 a3 fd ff ff e8 78 a8 83 02 85 c0 0f 84 5c 0a 00 00 48 c7
RSP: 0018:ffffc900034c7900 EFLAGS: 00010046
RAX: be8ef0697e996500 RBX: 0000000000001a46 RCX: ffff888020843b80
RDX: dffffc0000000000 RSI: 0000000080000001 RDI: 0000000000000000
RBP: ffffc900034c7b50 R08: ffff8880b912795b R09: 1ffff11017224f2b
R10: dffffc0000000000 R11: ffffed1017224f2c R12: ffff888020844690
R13: ffff888020843b80 R14: 0000000000000000 R15: ffff888020844670
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa2c2043eb8 CR3: 0000000064955000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
finish_wait+0xb5/0x1d0 kernel/sched/wait.c:407
gfs2_quotad+0x710/0x890 fs/gfs2/quota.c:1605
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>


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