INFO: task udevd:7512 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:23040 pid:7512 ppid:3637 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x10ec/0x40b0 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+0x6e1/0xf60 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+0xb4/0x870 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+0x7bd/0x1480 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+0x25c6/0x2e70 fs/namei.c:3791
do_filp_open+0x1c1/0x3c0 fs/namei.c:3818
do_sys_openat2+0x142/0x490 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: 0033:0x7fe2b0aa7407
RSP: 002b:00007ffec4c82100 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fe2b11aa880 RCX: 00007fe2b0aa7407
RDX: 00000000000a0800 RSI: 00005617ad76f430 RDI: ffffffffffffff9c
RBP: 00005617ad76e910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005617ad78bf10
R13: 00005617ad786410 R14: 0000000000000000 R15: 00005617ad78bf10
</TASK>
INFO: task udevd:7923 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:23488 pid:7923 ppid:3637 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x10ec/0x40b0 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+0x6e1/0xf60 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+0xb4/0x870 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+0x7bd/0x1480 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+0x25c6/0x2e70 fs/namei.c:3791
do_filp_open+0x1c1/0x3c0 fs/namei.c:3818
do_sys_openat2+0x142/0x490 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: 0033:0x7fe2b0aa7407
RSP: 002b:00007ffec4c82100 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fe2b11aa880 RCX: 00007fe2b0aa7407
RDX: 00000000000a0800 RSI: 00005617ad77f630 RDI: ffffffffffffff9c
RBP: 00005617ad76e910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005617ad783830
R13: 00005617ad786410 R14: 0000000000000000 R15: 00005617ad783830
</TASK>
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8c92bb70 (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: ffffffff8c92c390 (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/27:
#0: ffffffff8c92b1e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8c92b1e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8c92b1e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
2 locks held by getty/4029:
#0: ffff88814d17d098 (&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+0x41b/0x1380 drivers/tty/n_tty.c:2198
2 locks held by kworker/u4:15/4643:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90004567d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
1 lock held by udevd/7512:
#0: ffff888024de34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x13d/0xa60 block/bdev.c:832
1 lock held by udevd/7923:
#0: ffff8881437834c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x13d/0xa60 block/bdev.c:832
2 locks held by kworker/u4:25/12324:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc9000e917d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
2 locks held by kworker/u4:29/12329:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
<TASK>
dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3f4/0x470 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
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4256 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__update_blocked_others kernel/sched/pelt.h:-1 [inline]
RIP: 0010:update_blocked_averages+0x271/0x1560 kernel/sched/fair.c:8837
Code: 00 00 48 8d b8 90 0a 00 00 48 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 05 e8 54 80 74 00 4c 89 7c 24 48 <48> 8b 4c 24 10 48 8d 99 18 0a 00 00 48 89 d8 48 c1 e8 03 4c 2b b1
RSP: 0018:ffffc90003c07740 EFLAGS: 00000046
RAX: 1ffff110171e76b2 RBX: 000000010001da87 RCX: dffffc0000000000
RDX: 1ffffffff1efc008 RSI: ffffffff8a6c1780 RDI: ffff8880b8f3b590
RBP: ffffc90003c078c0 R08: ffffffff8f7e0048 R09: ffffffff8f7e0058
R10: ffffffff8f7e0050 R11: ffffffff8f7e0043 R12: 1ffff110171e7571
R13: 00000000000e5531 R14: 00000154e6b8f001 R15: ffff8880b8f3b858
FS: 000055555b7be500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6ca83b7198 CR3: 00000000775d5000 CR4: 00000000003506e0
DR0: 0000000000000008 DR1: 0000000000000002 DR2: 0000000000000404
DR3: ffffffffefffff18 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
sched_balance_newidle+0x55b/0x13b0 kernel/sched/fair.c:11627
pick_next_task_fair+0x27c/0xdf0 kernel/sched/fair.c:7912
__pick_next_task kernel/sched/core.c:5871 [inline]
pick_next_task kernel/sched/core.c:5946 [inline]
__schedule+0x6a6/0x40b0 kernel/sched/core.c:6525
schedule+0xb9/0x180 kernel/sched/core.c:6638
do_nanosleep+0x1a9/0x5f0 kernel/time/hrtimer.c:2088
hrtimer_nanosleep+0x15b/0x340 kernel/time/hrtimer.c:2136
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1314 [inline]
__se_sys_clock_nanosleep+0x2e6/0x370 kernel/time/posix-timers.c:1291
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: 0033:0x7fa4d51c1fc3
Code: 1f 84 00 00 00 00 00 83 ff 03 74 7b 83 ff 02 b8 fa ff ff ff 49 89 ca 0f 44 f8 80 3d 9e 95 1f 00 00 74 14 b8 e6 00 00 00 0f 05 <f7> d8 c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec 28 48 89 54 24 10
RSP: 002b:00007ffcea34af58 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fa4d51c1fc3
RDX: 00007ffcea34af70 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 00000000000005ea R09: 002420c0c2761ffa
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffcea34b3c0
R13: 0000000000000004 R14: 00007ffcea34afac R15: 00007ffcea34b040
</TASK>