INFO: task kworker/u8:10:1414 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:10 state:D stack:17688 pid:1414 tgid:1414 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1480/0x50a0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
afs_cell_purge+0x3f1/0x540 fs/afs/cell.c:921
afs_net_exit+0x50/0x100 fs/afs/main.c:147
ops_exit_list net/core/net_namespace.c:199 [inline]
ops_undo_list+0x49a/0x990 net/core/net_namespace.c:252
cleanup_net+0x4de/0x7b0 net/core/net_namespace.c:696
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:3/58:
2 locks held by kworker/u8:5/86:
#0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc9000157fb80 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000157fb80 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
3 locks held by kworker/u8:10/1414:
#0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc90004f0fb80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90004f0fb80 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8e896200 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7b0 net/core/net_namespace.c:670
4 locks held by kworker/u8:16/3501:
1 lock held by udevd/5169:
2 locks held by getty/5560:
#0: ffff8880344f20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211
2 locks held by kworker/u8:19/6035:
10 locks held by syz-executor/13555:
1 lock held by udevd/13895:
#0: ffff888021d85528 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline]
#0: ffff888021d85528 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_read_iter+0x2ff/0x440 block/fops.c:855
2 locks held by udevd/14135:
2 locks held by kworker/u8:25/14570:
2 locks held by syz.9.1331/15498:
#0: ffff888029e1a0d0 (&type->s_umount_key#51/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xab0 fs/super.c:344
#1: ffffffff8d456978 (wq_pool_mutex){+.+.}-{4:4}, at: apply_wqattrs_lock kernel/workqueue.c:5215 [inline]
#1: ffffffff8d456978 (wq_pool_mutex){+.+.}-{4:4}, at: __alloc_workqueue+0xa07/0x1b80 kernel/workqueue.c:5768
3 locks held by syz.5.1334/15505:
2 locks held by syz.5.1334/15512:
#0: ffff888020bb2480 (sb_writers#4){++++}-{0:0}, at: file_start_write include/linux/fs.h:2681 [inline]
#0: ffff888020bb2480 (sb_writers#4){++++}-{0:0}, at: vfs_fallocate+0x5f9/0x7f0 fs/open.c:338
#1: ffff8880484e5808 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
#1: ffff8880484e5808 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: ext4_fallocate+0x1e3/0x3d0 fs/ext4/extents.c:4792
3 locks held by syz.1.1335/15507:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 13938 Comm: udevd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x0/0xa0 kernel/kcov.c:299
Code: 7c 0a 10 48 89 74 0a 18 48 89 44 0a 20 c3 cc cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 a0 b1 91 65 44 8b 05 87
RSP: 0018:ffffc9000496f520 EFLAGS: 00000246
RAX: 0000000000000001 RBX: dffffc0000000000 RCX: ffffffff843bd2af
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffff88802e848690 R08: ffff88802e8486c7 R09: 1ffff11005d090d8
R10: dffffc0000000000 R11: ffffed1005d090d9 R12: ffff88802e8486b0
R13: 00000000000000b0 R14: 00000000000000af R15: 0000000000000001
FS: 00007f930896c880(0000) GS:ffff888126e06000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0600e7b000 CR3: 0000000069a0a000 CR4: 00000000003526f0
Call Trace:
variable_test_bit arch/x86/include/asm/bitops.h:222 [inline]
arch_test_bit arch/x86/include/asm/bitops.h:233 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
tomoyo_check_acl+0x2f8/0x400 security/tomoyo/domain.c:184
tomoyo_path_permission+0x1b4/0x380 security/tomoyo/file.c:586
tomoyo_check_open_permission+0x24d/0x3b0 security/tomoyo/file.c:777
security_file_open+0xb1/0x270 security/security.c:2636
do_dentry_open+0x35c/0x1270 fs/open.c:939
vfs_open+0x3b/0x350 fs/open.c:1094
do_open fs/namei.c:4628 [inline]
path_openat+0x342a/0x3df0 fs/namei.c:4787
do_filp_open+0x1fa/0x410 fs/namei.c:4814
do_sys_openat2+0x121/0x200 fs/open.c:1430
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1447
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9308a5a407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffdeac46a10 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f930896c880 RCX: 00007f9308a5a407
RDX: 0000000000080000 RSI: 00007ffdeac46b90 RDI: ffffffffffffff9c
RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000561512ac67f5
R13: 0000561512ac67f5 R14: 0000000000000001 R15: 0000561512ae1140