INFO: task udevd:5235 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:23440 pid:5235 ppid:3638 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
io_schedule+0x7c/0xd0 kernel/sched/core.c:8798
folio_wait_bit_common+0x70a/0xfa0 mm/filemap.c:1324
folio_put_wait_locked mm/filemap.c:1493 [inline]
do_read_cache_folio+0x1a9/0x760 mm/filemap.c:3641
read_mapping_folio include/linux/pagemap.h:799 [inline]
read_part_sector+0xce/0x350 block/partitions/core.c:724
adfspart_check_POWERTEC+0xc0/0x890 block/partitions/acorn.c:454
check_partition block/partitions/core.c:146 [inline]
blk_add_partitions block/partitions/core.c:609 [inline]
bdev_disk_changed+0x7d9/0x14a0 block/partitions/core.c:695
blkdev_get_whole+0x2e8/0x370 block/bdev.c:704
blkdev_get_by_dev+0x32e/0xa60 block/bdev.c:841
blkdev_open+0x11e/0x2e0 block/fops.c:500
do_dentry_open+0x7e9/0x10d0 fs/open.c:882
do_open fs/namei.c:3634 [inline]
path_openat+0x2635/0x2ee0 fs/namei.c:3791
do_filp_open+0x1f1/0x430 fs/namei.c:3818
do_sys_openat2+0x150/0x4b0 fs/open.c:1320
do_sys_open fs/open.c:1336 [inline]
__do_sys_openat fs/open.c:1352 [inline]
__se_sys_openat fs/open.c:1347 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1347
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1c454a7407
RSP: 002b:00007fff27c38a50 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f1c45b7f880 RCX: 00007f1c454a7407
RDX: 00000000000a0800 RSI: 000055bb5dd08980 RDI: ffffffffffffff9c
RBP: 000055bb5dcdf910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055bb5dd066d0
R13: 000055bb5dcf7410 R14: 0000000000000000 R15: 000055bb5dd066d0
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2dfb0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2e7d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
3 locks held by kworker/u4:5/2937:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#1: ffffc9000cdf7d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#2: ffffffff8cb332f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#2: ffffffff8cb332f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962
2 locks held by getty/4031:
#0: ffff88814d4ce098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x429/0x1390 drivers/tty/n_tty.c:2198
1 lock held by udevd/5235:
#0: ffff888024f544c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x13d/0xa60 block/bdev.c:832
2 locks held by kworker/1:14/5400:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#1: ffffc9000c5ffd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
2 locks held by kworker/1:19/11413:
#0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#1: ffffc90003cafd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
2 locks held by syz-executor/11926:
#0: ffff88807a20c0e0 (&type->s_umount_key#71){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:362
#1: ffffffff8cb332f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#1: ffffffff8cb332f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962
2 locks held by dhcpcd-run-hook/16357:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xeee/0xf30 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 16360 Comm: sed Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:set_canary_byte mm/kfence/core.c:305 [inline]
RIP: 0010:for_each_canary mm/kfence/core.c:351 [inline]
RIP: 0010:kfence_guarded_alloc+0x9d5/0xe40 mm/kfence/core.c:439
Code: c3 00 10 00 00 4c 89 f7 48 89 de e8 c5 e3 ae ff 49 39 de 4c 8b 6c 24 18 73 3d 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 75 19 <44> 89 f0 24 07 34 aa 41 88 06 49 ff c6 49 39 de 73 22 e8 b4 e1 ae
RSP: 0018:ffffc9000c67f640 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88823bc4b000 RCX: ffff888076209dc0
RDX: 0000000000000000 RSI: ffff88823bc4b000 RDI: ffff88823bc4a098
RBP: ffffc9000c67f770 R08: ffffea0008ef1287 R09: 1ffffd40011de250
R10: dffffc0000000000 R11: fffff940011de251 R12: dffffc0000000000
R13: ffff88823bc4a000 R14: ffff88823bc4a700 R15: ffff888140008b40
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff5a58c80a0 CR3: 000000005c187000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__kfence_alloc+0x396/0x3d0 mm/kfence/core.c:1065
kfence_alloc include/linux/kfence.h:128 [inline]
slab_alloc_node mm/slub.c:3283 [inline]
slab_alloc mm/slub.c:3367 [inline]
__kmem_cache_alloc_lru mm/slub.c:3374 [inline]
kmem_cache_alloc+0x287/0x2f0 mm/slub.c:3383
vm_area_alloc+0x20/0xe0 kernel/fork.c:459
__mmap_region mm/mmap.c:2753 [inline]
mmap_region+0xc18/0x1ca0 mm/mmap.c:2916
do_mmap+0x964/0xfd0 mm/mmap.c:1436
vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:520
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ff5a5ba9242
Code: 08 00 04 00 00 eb e2 90 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 33 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5e 5b 5d c3 0f 1f 00 c7 05 46 40 01 00 16 00
RSP: 002b:00007ffe48700a08 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007ff5a58c9000 RCX: 00007ff5a5ba9242
RDX: 0000000000000003 RSI: 0000000000001888 RDI: 00007ff5a58c9000
RBP: 0000000000000032 R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000000032 R11: 0000000000000206 R12: 00007ffe48700ac8
R13: 00007ff5a5b86580 R14: 00007ffe48700e80 R15: 00007ff5a58c9000
vkms_vblank_simulate: vblank timer overrun