[syzbot] [gfs2?] WARNING in dlm_lowcomms_connect_node

[syzbot <syzbot+d451adc04b34fbabccf2@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    21d6ac051080 Merge branch 'for-next/core' into for-kernelci
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=14bbea25580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d1128bc53f2ef7f3
dashboard link: https://syzkaller.appspot.com/bug?extid=d451adc04b34fbabccf2
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/88380e2ddcb9/disk-21d6ac05.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5dba5c2896b7/vmlinux-21d6ac05.xz
kernel image: https://storage.googleapis.com/syzbot-assets/52ac739e37e0/Image-21d6ac05.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d451adc04b34fbabccf2@syzkaller.appspotmail.com

dlm: ls1: dlm_recover 15333067685668308026
------------[ cut here ]------------
WARNING: fs/dlm/lowcomms.c:557 at dlm_lowcomms_connect_node+0x14c/0x1f8 fs/dlm/lowcomms.c:558, CPU#0: dlm_recoverd/4971
Modules linked in:
CPU: 0 UID: 0 PID: 4971 Comm: dlm_recoverd Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : dlm_lowcomms_connect_node+0x14c/0x1f8 fs/dlm/lowcomms.c:558
lr : __find_con fs/dlm/lowcomms.c:274 [inline]
lr : nodeid2con fs/dlm/lowcomms.c:305 [inline]
lr : dlm_lowcomms_connect_node+0x114/0x1f8 fs/dlm/lowcomms.c:556
sp : ffff8000933b7b20
x29: ffff8000933b7b20 x28: 0000000000000002 x27: 0000000000000001
x26: ffff0000ee849000 x25: ffff0000ef82f480 x24: dfff800000000000
x23: 0000000000000000 x22: ffff80008e8f5c50 x21: 0000000000000002
x20: ffff800088ed2bc0 x19: 0000000000000000 x18: 00000000ffffffff
x17: ffff80008a7d6000 x16: 0000000000000003 x15: ffff80008a35fda0
x14: ffff80008a5d5e28 x13: ffff0000cf590000 x12: ffff0000cf590000
x11: 00000000000000c8 x10: 0000000000000003 x9 : 0000000000000000
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffff80008aa48520 x4 : 0000000000000004 x3 : 0000000000000001
x2 : ffff80008a468b28 x1 : ffff0000cf590000 x0 : 0000000000000000
Call trace:
 dlm_lowcomms_connect_node+0x14c/0x1f8 fs/dlm/lowcomms.c:558 (P)
 add_remote_member fs/dlm/member.c:313 [inline]
 dlm_add_member fs/dlm/member.c:334 [inline]
 dlm_recover_members+0xe98/0x1c48 fs/dlm/member.c:607
 ls_recover fs/dlm/recoverd.c:151 [inline]
 do_ls_recovery fs/dlm/recoverd.c:360 [inline]
 dlm_recoverd+0x594/0x1d20 fs/dlm/recoverd.c:430
 kthread+0x304/0x3d4 kernel/kthread.c:436
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:838
irq event stamp: 46
hardirqs last  enabled at (45): [<ffff800086930818>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline]
hardirqs last  enabled at (45): [<ffff800086930818>] _raw_spin_unlock_irqrestore+0x38/0x98 kernel/locking/spinlock.c:198
hardirqs last disabled at (46): [<ffff80008690b3d0>] el1_brk64+0x20/0x54 arch/arm64/kernel/entry-common.c:445
softirqs last  enabled at (42): [<ffff800080f722fc>] dlm_create_root_list fs/dlm/recoverd.c:72 [inline]
softirqs last  enabled at (42): [<ffff800080f722fc>] ls_recover fs/dlm/recoverd.c:141 [inline]
softirqs last  enabled at (42): [<ffff800080f722fc>] do_ls_recovery fs/dlm/recoverd.c:360 [inline]
softirqs last  enabled at (42): [<ffff800080f722fc>] dlm_recoverd+0x584/0x1d20 fs/dlm/recoverd.c:430
softirqs last disabled at (40): [<ffff800080f721ec>] dlm_create_root_list fs/dlm/recoverd.c:65 [inline]
softirqs last disabled at (40): [<ffff800080f721ec>] ls_recover fs/dlm/recoverd.c:141 [inline]
softirqs last disabled at (40): [<ffff800080f721ec>] do_ls_recovery fs/dlm/recoverd.c:360 [inline]
softirqs last disabled at (40): [<ffff800080f721ec>] dlm_recoverd+0x474/0x1d20 fs/dlm/recoverd.c:430
---[ end trace 0000000000000000 ]---
dlm: ls1: dlm_recover_members error -2
dlm: ls1: do_ls_recovery 15333067685668308026 error -2
dlm: ls1: dlm_recover 15333067685668308027
dlm: ls1: add member 1
dlm: ls1: dlm_recover_members 1 nodes
dlm: ls1: generation 1 slots 1 1:1
dlm: ls1: dlm_recover_directory
dlm: ls1: dlm_recover_directory 0 in 0 new
dlm: ls1: dlm_recover 15333067685668308027 generation 1 done: 10 ms


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