[syzbot] [mm?] WARNING in shrink_lruvec

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2061f18ad76e Merge tag 'caps-pr-20251204' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=151cc41a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=879619bdbc37e7fc
dashboard link: https://syzkaller.appspot.com/bug?extid=90fcab4d88cffed6d0d8
compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5fcfff6f18cf/disk-2061f18a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/36b7247e87d2/vmlinux-2061f18a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e2f1eee5ec54/bzImage-2061f18a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+90fcab...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: mm/vmscan.c:5049 at lru_gen_shrink_lruvec mm/vmscan.c:5049 [inline], CPU#1: syz.0.6406/391
WARNING: mm/vmscan.c:5049 at shrink_lruvec+0x253b/0x2b50 mm/vmscan.c:5818, CPU#1: syz.0.6406/391
Modules linked in:
CPU: 1 UID: 0 PID: 391 Comm: syz.0.6406 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:lru_gen_shrink_lruvec mm/vmscan.c:5049 [inline]
RIP: 0010:shrink_lruvec+0x253b/0x2b50 mm/vmscan.c:5818
Code: 89 de e8 78 78 bf ff 49 8d 46 34 48 89 44 24 38 84 db 0f 84 cf 00 00 00 31 ff b9 02 00 00 00 e9 42 df ff ff e8 06 7e bf ff 90 <0f> 0b 90 e9 45 dd ff ff 48 8b bc 24 98 00 00 00 e8 e0 90 27 00 e9
RSP: 0018:ffffc9000d5def60 EFLAGS: 00010283
RAX: 0000000000001170 RBX: ffffc9000d5df120 RCX: ffffc90014135000
RDX: 0000000000080000 RSI: ffffffff81fe1a6a RDI: 0000000000000001
RBP: ffffc9000d5df2e0 R08: 0000000000000001 R09: 0000000000000030
R10: 0000000000000020 R11: 00000000622d1f49 R12: 0000000000000020
R13: ffff88807cd00d40 R14: ffffc9000d5df628 R15: 1ffff92001abbe0a
FS: 00007f36a7b6f6c0(0000) GS:ffff888124a67000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30008ff8 CR3: 000000005c3e2000 CR4: 00000000003526f0
Call Trace:
<TASK>
shrink_node_memcgs mm/vmscan.c:6054 [inline]
shrink_node+0x988/0x3da0 mm/vmscan.c:6095
shrink_zones mm/vmscan.c:6339 [inline]
do_try_to_free_pages+0x362/0x1920 mm/vmscan.c:6401
try_to_free_mem_cgroup_pages+0x31b/0x740 mm/vmscan.c:6729
mem_cgroup_resize_max+0x113/0x2b0 mm/memcontrol-v1.c:1480
mem_cgroup_write+0x295/0x3a0 mm/memcontrol-v1.c:1662
cgroup_file_write+0x1ef/0x7a0 kernel/cgroup/cgroup.c:4312
kernfs_fop_write_iter+0x3af/0x570 fs/kernfs/file.c:352
iter_file_splice_write+0xa24/0x12b0 fs/splice.c:738
do_splice_from fs/splice.c:938 [inline]
direct_splice_actor+0x192/0x6c0 fs/splice.c:1161
splice_direct_to_actor+0x345/0xa30 fs/splice.c:1105
do_splice_direct_actor fs/splice.c:1204 [inline]
do_splice_direct+0x174/0x240 fs/splice.c:1230
do_sendfile+0xb06/0xe50 fs/read_write.c:1370
__do_sys_sendfile64 fs/read_write.c:1431 [inline]
__se_sys_sendfile64 fs/read_write.c:1417 [inline]
__x64_sys_sendfile64+0x1d8/0x220 fs/read_write.c:1417
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f36a6d8f7c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f36a7b6f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f36a6fe5fa0 RCX: 00007f36a6d8f7c9
RDX: 0000000000000000 RSI: 000000000000000b RDI: 000000000000000b
RBP: 00007f36a6e13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f36a6fe6038 R14: 00007f36a6fe5fa0 R15: 00007ffd83c52c98
</TASK>


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