INFO: task udevd:32712 blocked for more than 143 seconds.
Not tainted syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:23520 pid:32712 tgid:32712 ppid:5190 task_flags:0x40054c flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6908
__schedule_loop kernel/sched/core.c:6990 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7005
io_schedule+0x7f/0xd0 kernel/sched/core.c:7832
folio_wait_bit_common+0x6d8/0xbc0 mm/filemap.c:1323
__folio_lock mm/filemap.c:1699 [inline]
folio_lock include/linux/pagemap.h:1170 [inline]
__filemap_get_folio_mpol+0x13e/0xb00 mm/filemap.c:1954
__filemap_get_folio include/linux/pagemap.h:774 [inline]
truncate_inode_pages_range+0x48b/0xe30 mm/truncate.c:413
kill_bdev block/bdev.c:91 [inline]
blkdev_flush_mapping+0x109/0x2f0 block/bdev.c:728
blkdev_put_whole block/bdev.c:735 [inline]
bdev_release+0x417/0x650 block/bdev.c:1160
blkdev_release+0x15/0x20 block/fops.c:705
__fput+0x44f/0xa70 fs/file_table.c:469
task_work_run+0x1d9/0x270 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x70f/0x23c0 kernel/exit.c:976
do_group_exit+0x21b/0x2d0 kernel/exit.c:1118
get_signal+0x1284/0x1330 kernel/signal.c:3034
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9cedaa7407
RSP: 002b:00007ffdf9dfd590 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: fffffffffffffffc RBX: 00007f9cee1ed880 RCX: 00007f9cedaa7407
RDX: 0000000000000200 RSI: 00007f9cee1ec000 RDI: 0000000000000009
RBP: 000055ffccde6050 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 000055ffccdf4aa8 R15: 00007f9cee31439c
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5578:
#0: ffff888036c320a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by kworker/1:7/5888:
#0: ffff88813fe0f548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff88813fe0f548 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
#1: ffffc900046b7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc900046b7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
#2: ffff888030168240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x202/0x3d0 drivers/net/netdevsim/fib.c:1490
1 lock held by udevd/32712:
#0: ffff888034bfd358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1144
1 lock held by udevd/32714:
#0: ffff888026e94358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:961
1 lock held by udevd/2406:
#0: ffff888026f56358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:961
3 locks held by syz.3.12623/20008:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [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+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 20008 Comm: syz.3.12623 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:preempt_count_sub+0x3f/0x170 kernel/sched/core.c:5790
Code: 27 9a 48 c1 e8 03 0f b6 04 18 84 c0 0f 85 c5 00 00 00 83 3d 72 2c 93 18 00 75 25 65 8b 05 19 c8 87 11 89 c1 81 e1 ff ff ff 7f <39> cf 7f 2a 81 ff ff 00 00 00 0f 93 c1 84 c0 0f 95 c0 08 c8 74 58
RSP: 0018:ffffc9000d42f6b0 EFLAGS: 00000202
RAX: 0000000080000201 RBX: dffffc0000000000 RCX: 0000000000000201
RDX: 0000000000000001 RSI: ffffffff8e169e19 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffffffff89c03b35 R09: ffffffff8e7603a0
R10: 0000000000000004 R11: 0000000000000002 R12: 0000000000000008
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff88813fef1180
FS: 00007f826afaa6c0(0000) GS:ffff888125465000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5b8feca7d0 CR3: 0000000075cd8000 CR4: 00000000003526f0
Call Trace:
rcu_read_unlock_sched include/linux/rcupdate.h:975 [inline]
pfn_valid+0x427/0x4c0 include/linux/mmzone.h:2207
xdp_test_run_batch net/bpf/test_run.c:301 [inline]
bpf_test_run_xdp_live+0x74e/0x1cf0 net/bpf/test_run.c:379
bpf_prog_test_run_xdp+0x81c/0x1160 net/bpf/test_run.c:1397
bpf_prog_test_run+0x2c7/0x340 kernel/bpf/syscall.c:4722
__sys_bpf+0x643/0x950 kernel/bpf/syscall.c:6246
__do_sys_bpf kernel/bpf/syscall.c:6341 [inline]
__se_sys_bpf kernel/bpf/syscall.c:6339 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6339
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f826a19c799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f826afaa028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f826a415fa0 RCX: 00007f826a19c799
RDX: 0000000000000048 RSI: 0000200000000600 RDI: 000000000000000a
RBP: 00007f826a232bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f826a416038 R14: 00007f826a415fa0 R15: 00007ffdf86b9488