INFO: task udevd:5634 blocked in I/O wait for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:23400 pid:5634 tgid:5634 ppid:4977 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d4/0x5630 kernel/sched/core.c:7239
__schedule_loop kernel/sched/core.c:7316 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7331
io_schedule+0x7f/0xd0 kernel/sched/core.c:8159
folio_wait_bit_common+0x836/0xbc0 mm/filemap.c:1329
folio_put_wait_locked mm/filemap.c:1498 [inline]
do_read_cache_folio+0x1ac/0x590 mm/filemap.c:4128
read_mapping_folio include/linux/pagemap.h:1015 [inline]
read_part_sector+0xb6/0x2b0 block/partitions/core.c:724
adfspart_check_POWERTEC+0x9a/0x7a0 block/partitions/acorn.c:451
check_partition block/partitions/core.c:143 [inline]
blk_add_partitions block/partitions/core.c:591 [inline]
bdev_disk_changed+0x851/0x17a0 block/partitions/core.c:695
blkdev_get_whole+0x372/0x510 block/bdev.c:794
bdev_open+0x324/0xd70 block/bdev.c:1003
blkdev_open+0x461/0x600 block/fops.c:674
do_dentry_open+0x816/0x1380 fs/open.c:996
vfs_open+0x3b/0x340 fs/open.c:1101
do_open fs/namei.c:4837 [inline]
path_openat+0x1443/0x1d60 fs/namei.c:5000
do_file_open+0x23e/0x4a0 fs/namei.c:5029
do_sys_openat2+0x115/0x200 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_openat fs/open.c:1439 [inline]
__se_sys_openat fs/open.c:1434 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1434
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8fce2a7407
RSP: 002b:00007ffd1dfcd050 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f8fce98f880 RCX: 00007f8fce2a7407
RDX: 00000000000a0800 RSI: 000055bad24330f0 RDI: ffffffffffffff9c
RBP: 000055bad241b910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055bad2430830
R13: 000055bad2429190 R14: 0000000000000000 R15: 000055bad2430830
Showing all locks held in the system:
locks held by khungtaskd/30: 1, last CPU#1:
#0: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6793
locks held by kworker/u8:7/1092: 3, last CPU#0:
#0: ffff8880b863b4e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667
#1: ffff8880b8624408 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933
#2: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#2: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#2: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rds_queue_reconnect+0x213/0x8c0 net/rds/threads.c:152
locks held by getty/5367: 2, on CPU#0:
#0: ffff888035e6e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by udevd/5634: 1, on CPU#0:
#0: ffff888027df2350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70 block/bdev.c:991
locks held by kworker/u8:14/6191: 3, last CPU#0:
#0: ffff8880b863b4e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667
#1: ffff8880b8624408 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933
#2: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#2: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#2: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rds_queue_reconnect+0x213/0x8c0 net/rds/threads.c:152
locks held by kworker/u8:25/12272: 3, last CPU#0:
#0: ffff8880207b0940 ((wq_completion)krds_cp_wq#18/1){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff8880207b0940 ((wq_completion)krds_cp_wq#18/1){+.+.}-{0:0}, at: process_scheduled_works+0xa1a/0x14c0 kernel/workqueue.c:3405
#1: ffff8880b8624408 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933
#2: ffff8880b8626018 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline]
#2: ffff8880b8626018 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1a9/0xed0 kernel/time/timer.c:1085
locks held by syz.0.5012/24463: 1, on CPU#1:
#0: ffff888048ac7b00 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1025 [inline]
#0: ffff888048ac7b00 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x7a/0x1f0 net/socket.c:734
locks held by syz.3.5013/24465: 1, on CPU#0:
#0: ffffffff90036380 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:650 [inline]
#0: ffffffff90036380 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3587
locks held by syz.1.5010/24467: 1, on CPU#0:
#0: ffff888048bc1380 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1025 [inline]
#0: ffff888048bc1380 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x7a/0x1f0 net/socket.c:734
locks held by syz.1.5010/24469: 1, on CPU#0:
#0: ffffffff90039c80 (bpf_dispatcher_xdp.mutex){+.+.}-{4:4}, at: bpf_dispatcher_change_prog+0xc2/0xf20 kernel/bpf/dispatcher.c:146
locks held by syz.1.5010/24476: 2, on CPU#0:
#0: ffff8880323e34d0 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x3b/0x100 net/netfilter/nf_tables_api.c:11512
#1: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
locks held by syz.2.5014/24473: 1, on CPU#1:
#0: ffff8880571769c0 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1025 [inline]
#0: ffff8880571769c0 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x7a/0x1f0 net/socket.c:734
locks held by syz.2.5014/24474: 1, on CPU#1:
#0: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#0: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
=============================================
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 07/24/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [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:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 23247 Comm: kworker/0:8 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: rcu_gp process_srcu
RIP: 0010:delay_tsc+0x6c/0xd0 arch/x86/lib/delay.c:88
Code: 73 55 bf 01 00 00 00 e8 92 4d bd f5 65 48 8b 05 8a a6 98 07 48 85 c0 74 1c f3 90 bf 01 00 00 00 e8 29 4c bd f5 e8 14 78 01 00 <39> c5 75 0e 0f 01 f9 66 90 eb bb e8 b4 3b 5c f5 eb dd 4c 29 fb e8
RSP: 0018:ffffc9000f2d7928 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000002af9 RCX: 8000000000000001
RDX: 0000000000000101 RSI: ffffffff8c4cd760 RDI: ffffffff8c4cd720
RBP: 0000000000000000 R08: ffff8880b8743517 R09: 1ffff110170e86a2
R10: dffffc0000000000 R11: ffffffff8bd71930 R12: 0000000000000001
R13: 0000000000000001 R14: 0000019b888a2420 R15: 00000000000026b1
FS: 0000000000000000(0000) GS:ffff888124f24000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9d4cff14b8 CR3: 000000005ec9c000 CR4: 00000000003526f0
Call Trace:
udelay include/asm-generic/delay.h:64 [inline]
try_check_zero+0x439/0x4c0 kernel/rcu/srcutree.c:1158
srcu_advance_state kernel/rcu/srcutree.c:1864 [inline]
process_srcu+0x328/0x16f0 kernel/rcu/srcutree.c:1973
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa88/0x14c0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
IPVS: ovf: UDP 224.0.0.2:0 - no destination available