INFO: task udevd:5136 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:23144 pid:5136 ppid:1 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6832
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b7/0xcc0 kernel/locking/mutex.c:747
blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
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+0x274b/0x3190 fs/namei.c:3797
do_filp_open+0x1c5/0x3d0 fs/namei.c:3824
do_sys_openat2+0x12c/0x1c0 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:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f778c6a7407
RSP: 002b:00007ffc7d6492a0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f778ce88880 RCX: 00007f778c6a7407
RDX: 00000000000a0800 RSI: 0000556462728190 RDI: ffffffffffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00005564258ca100 R14: 0000000000000000 R15: 00007ffc7d649530
INFO: task syz.4.464:8062 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.464 state:D stack:27760 pid:8062 ppid:7244 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6832
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b7/0xcc0 kernel/locking/mutex.c:747
blkdev_put+0xff/0x760 block/bdev.c:944
blkdev_release+0x84/0x90 block/fops.c:604
__fput+0x234/0x970 fs/file_table.c:384
task_work_run+0x1ce/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7efd7a78f749
RSP: 002b:00007efd7b5dc038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007efd7a9e6090 RCX: 00007efd7a78f749
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000004
RBP: 00007efd7a813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efd7a9e6128 R14: 00007efd7a9e6090 R15: 00007ffc9a5ae1c8
Showing all locks held in the system:
1 lock held by khungtaskd/29:
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
3 locks held by kworker/u4:3/49:
2 locks held by kworker/u4:8/1085:
1 lock held by udevd/5136:
#0: ffff8881413984c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
2 locks held by getty/5525:
#0: ffff88814caca0a0 (&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+0x425/0x1380 drivers/tty/n_tty.c:2217
2 locks held by kworker/0:5/5882:
#0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc90004a5fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90004a5fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
1 lock held by udevd/5920:
#0: ffff8881413984c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
1 lock held by syz.4.464/8062:
#0: ffff8881413984c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xff/0x760 block/bdev.c:944
1 lock held by syz.9.815/9907:
#0: ffffffff8cd357c0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:4089
1 lock held by dhcpcd-run-hook/9924:
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x39b/0x3d0 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+0xf41/0xf80 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9928 Comm: sed Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4787 [inline]
RIP: 0010:__lock_acquire+0x6cc/0x7c80 kernel/locking/lockdep.c:5087
Code: 01 80 0f 85 56 05 00 00 84 db 41 0f b6 c6 0f b6 cb 0f 44 c8 89 4c 24 38 48 8b 44 24 78 42 0f b6 04 00 84 c0 0f 85 a9 64 00 00 <45> 8b bd d8 0a 00 00 41 8d 47 ff 83 f8 ff 41 bc ff ff ff ff 44 0f
RSP: 0000:ffffc90004e1f640 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90d94500
RBP: ffffc90004e1f888 R08: dffffc0000000000 R09: 1ffffffff21b28a0
R10: dffffc0000000000 R11: fffffbfff21b28a1 R12: ffff88802726a8c4
R13: ffff888027269e00 R14: 0000000000000002 R15: ffff88802726a9c8
FS: 00007f69fa8e7c80(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f69fac293f0 CR3: 0000000065e61000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
rcu_read_lock_sched include/linux/rcupdate.h:878 [inline]
pfn_valid+0xe9/0x420 include/linux/mmzone.h:2011
page_table_check_set+0x25/0x6f0 mm/page_table_check.c:110
page_table_check_ptes_set include/linux/page_table_check.h:74 [inline]
set_ptes include/linux/pgtable.h:238 [inline]
set_pte_range+0x679/0x6a0 mm/memory.c:4407
filemap_map_order0_folio mm/filemap.c:3599 [inline]
filemap_map_pages+0xe9b/0x1950 mm/filemap.c:3660
do_fault_around mm/memory.c:4595 [inline]
do_read_fault mm/memory.c:4628 [inline]
do_fault mm/memory.c:4775 [inline]
do_pte_missing mm/memory.c:3689 [inline]
handle_pte_fault mm/memory.c:5047 [inline]
__handle_mm_fault mm/memory.c:5188 [inline]
handle_mm_fault+0x379b/0x4920 mm/memory.c:5353
do_user_addr_fault+0xad0/0x12e0 arch/x86/mm/fault.c:1324
handle_page_fault arch/x86/mm/fault.c:1465 [inline]
exc_page_fault+0x67/0x110 arch/x86/mm/fault.c:1521
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f69fab096eb
Code: 59 fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 c4 41 01 ef ff 89 f8 09 f0 c1 e0 14 3d 00 00 00 f8 0f 87 29 03 00 00 c5 fe 6f 07 fd 74 0e c5 85 74 d0 c5 ed df c9 c5 fd d7 c9 ff c1 74 61 90 f3
RSP: 002b:00007ffe26c31948 EFLAGS: 00010283
RAX: 00000000fffffeb5 RBX: 0000558ee78f5000 RCX: 00000000000003f0
RDX: 0000000000000000 RSI: 00007f69fac293f0 RDI: 00007ffe26c32e35
RBP: 00007ffe26c31a98 R08: 0000000000000000 R09: 00007f69fac58a60
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe26c31ac0 R14: 00007f69fac89000 R15: 0000558ee78f6d98