INFO: task udevd:8894 blocked 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:24968 pid:8894 ppid:5142 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
io_schedule+0x80/0xd0 kernel/sched/core.c:9023
folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329
folio_put_wait_locked mm/filemap.c:1493 [inline]
do_read_cache_folio+0x1c0/0x7d0 mm/filemap.c:3791
read_mapping_folio include/linux/pagemap.h:898 [inline]
read_part_sector+0xd2/0x340 block/partitions/core.c:718
adfspart_check_POWERTEC+0x93/0xed0 block/partitions/acorn.c:454
check_partition block/partitions/core.c:138 [inline]
blk_add_partitions block/partitions/core.c:600 [inline]
bdev_disk_changed+0x740/0x1420 block/partitions/core.c:689
blkdev_get_whole+0x30d/0x390 block/bdev.c:672
blkdev_get_by_dev+0x279/0x600 block/bdev.c:814
blkdev_open+0x152/0x360 block/fops.c:589
do_dentry_open+0x8c6/0x1500 fs/open.c:929
do_open fs/namei.c:3640 [inline]
path_openat+0x27f1/0x3230 fs/namei.c:3797
do_filp_open+0x1f5/0x430 fs/namei.c:3824
do_sys_openat2+0x134/0x1d0 fs/open.c:1421
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+0x139/0x160 fs/open.c:1447
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd5ccea7407
RSP: 002b:00007ffd3b077850 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fd5cd5a9880 RCX: 00007fd5ccea7407
RDX: 00000000000a0800 RSI: 000055a371b12ff0 RDI: ffffffffffffff9c
RBP: 000055a371ae2910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055a371afc320
R13: 000055a371afa410 R14: 0000000000000000 R15: 000055a371afc320
Showing all locks held in the system:
4 locks held by kworker/1:0/23:
#0: ffff888147a47138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888147a47138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1: ffffc900001d7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc900001d7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#2: ffff8881433b51d8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1094 [inline]
#2: ffff8881433b51d8 (&dev->mutex){....}-{3:3}, at: hub_event+0x180/0x49f0 drivers/usb/core/hub.c:5861
#3: ffff88807aff51d8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1094 [inline]
#3: ffff88807aff51d8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x89/0x420 drivers/base/dd.c:1085
1 lock held by khungtaskd/29:
#0: ffffffff8d132160 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d132160 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d132160 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
2 locks held by kworker/u4:6/1128:
#0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1: ffffc9000479fd00 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000479fd00 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
2 locks held by getty/5537:
#0: ffff88802d25c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217
2 locks held by kworker/0:5/5823:
#0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1: ffffc9000484fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000484fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
3 locks held by kworker/u4:14/7034:
2 locks held by kworker/u4:23/7065:
#0: ffff88801ea8a138 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff88801ea8a138 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1: ffffc90004dbfd00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc90004dbfd00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
4 locks held by kworker/u4:27/7291:
#0: ffff88801a254938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff88801a254938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1: ffffc9000b8ffd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000b8ffd00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#2: ffffffff8e3b9990 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x14c/0xbb0 net/core/net_namespace.c:606
#3: ffff88805ee21468 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_destruct+0x116/0x310 drivers/net/wireguard/device.c:250
1 lock held by udevd/8894:
#0: ffff8880223f34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
3 locks held by kworker/1:3/9139:
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#1: ffffc90002e87d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc90002e87d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730
#2: ffff88801d7f0240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x286/0x31b0 drivers/net/netdevsim/fib.c:1491
4 locks held by udevd/9735:
#0: ffff88802eeda2f0 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xb1/0xd50 fs/seq_file.c:182
#1: ffff888064cea488 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x5c/0x410 fs/kernfs/file.c:172
#2: ffff888028728ca0 (kn->active#18){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888028728ca0 (kn->active#18){.+.+}-{0:0}, at: kernfs_seq_start+0xb2/0x410 fs/kernfs/file.c:173
#3: ffff88807aff51d8 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:1099 [inline]
#3: ffff88807aff51d8 (&dev->mutex){....}-{3:3}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
2 locks held by modprobe/10894:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf3d/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: kworker/1:1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events kfree_rcu_work
RIP: 0010:unwind_next_frame+0x1740/0x2970 arch/x86/kernel/unwind_orc.c:648
Code: 24 36 4c 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 0a 12 00 00 41 80 3f 01 0f 85 8b 04 00 00 e8 95 dc 4b 00 e9 ad 04 00 00 <4c> 8d 73 02 48 83 c3 03 4c 89 f0 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc90000a2f4f8 EFLAGS: 00000246
RAX: 0000000000000003 RBX: ffffffff8f1a4220 RCX: 0000000000000003
RDX: ffffffff813b4e99 RSI: ffffffff8cfa08a0 RDI: 0000000000000001
RBP: ffffc90000a2f618 R08: ffff88801ca53c00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000000 R12: ffffc90000a2f5c8
R13: dffffc0000000000 R14: 0000000000000001 R15: ffffffff8f1a4224
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2eec72a368 CR3: 000000000cf32000 CR4: 00000000003506e0
Call Trace:
arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1811 [inline]
slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
kmem_cache_free_bulk+0x33b/0x450 mm/slub.c:3948
kfree_bulk include/linux/slab.h:517 [inline]
kvfree_rcu_bulk+0x1eb/0x470 kernel/rcu/tree.c:3032
kfree_rcu_work+0x344/0x3b0 kernel/rcu/tree.c:3111
process_one_work kernel/workqueue.c:2653 [inline]
process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293