INFO: task udevd:4755 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:25264 pid: 4755 ppid: 3562 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
io_schedule+0x7c/0xd0 kernel/sched/core.c:8503
wait_on_page_bit_common+0x83b/0xe50 mm/filemap.c:1356
wait_on_page_bit mm/filemap.c:1417 [inline]
wait_on_page_locked include/linux/pagemap.h:688 [inline]
wait_on_page_read mm/filemap.c:3437 [inline]
do_read_cache_page+0xb05/0x1030 mm/filemap.c:3480
read_mapping_page include/linux/pagemap.h:515 [inline]
read_part_sector+0xd4/0x4f0 block/partitions/core.c:726
adfspart_check_ICS+0xc3/0xe40 block/partitions/acorn.c:360
check_partition block/partitions/core.c:148 [inline]
blk_add_partitions block/partitions/core.c:611 [inline]
bdev_disk_changed+0x933/0x16c0 block/partitions/core.c:697
blkdev_get_whole+0x2f9/0x390 block/bdev.c:682
blkdev_get_by_dev+0x2d0/0xa60 block/bdev.c:827
blkdev_open+0x12d/0x2c0 block/fops.c:466
do_dentry_open+0x7ff/0xf80 fs/open.c:826
do_open fs/namei.c:3616 [inline]
path_openat+0x26f5/0x2fa0 fs/namei.c:3750
do_filp_open+0x1e2/0x410 fs/namei.c:3777
do_sys_openat2+0x150/0x4b0 fs/open.c:1255
do_sys_open fs/open.c:1271 [inline]
__do_sys_openat fs/open.c:1287 [inline]
__se_sys_openat fs/open.c:1282 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1282
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f26f18d7407
RSP: 002b:00007ffd2eca5b40 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f26f17e9880 RCX: 00007f26f18d7407
RDX: 00000000000a0800 RSI: 0000560b71a614f0 RDI: ffffffffffffff9c
RBP: 0000560b71a37910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000560b71a4c830
R13: 0000560b71a4f410 R14: 0000000000000000 R15: 0000560b71a4c830
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:2/154:
2 locks held by getty/3948:
#0: ffff88814cc0d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900021ce2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
2 locks held by kworker/u4:15/4408:
1 lock held by udevd/4755:
#0: ffff8880210be918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
1 lock held by syz-executor/8470:
#0: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
#0: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845
2 locks held by kworker/1:20/9944:
#0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc900040f7d00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
2 locks held by syz-executor/10025:
#0: ffff888020a7a118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915
#1: ffff888020be4468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xaa/0xb90 drivers/block/loop.c:1366
1 lock held by sed/10521:
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 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+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4173 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:arch_static_branch include/trace/events/rcu.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:212 [inline]
RIP: 0010:trace_rcu_utilization+0x0/0x1a0 include/trace/events/rcu.h:27
Code: c7 c1 a4 d9 89 8d 80 e1 07 80 c1 03 38 c1 0f 8c de f7 ff ff 48 c7 c7 a4 d9 89 8d e8 1a 3e 59 00 e9 cd f7 ff ff 0f 1f 44 00 00 <41> 57 41 56 53 0f 1f 44 00 00 65 8b 05 37 2f 9d 7e 83 f8 08 0f 83
RSP: 0018:ffffc900026b7858 EFLAGS: 00000086
RAX: ffff8880b903b1c0 RBX: dffffc0000000000 RCX: a0aab6a2d21ed600
RDX: 0000000000000000 RSI: ffffffff8a79f760 RDI: ffffffff8a2c5960
RBP: ffffc900026b79d0 R08: ffffc900026b7b4f R09: ffffc900026b7b40
R10: dffffc0000000000 R11: fffff520004d6f6a R12: ffff888024360000
R13: 0000000000000000 R14: ffffffff8be30820 R15: 1ffff920004d6f28
FS: 0000555574843500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff91cbb758 CR3: 000000001ecb9000 CR4: 00000000003506f0
Call Trace:
rcu_note_context_switch+0xc5/0x1020 kernel/rcu/tree_plugin.h:314
__schedule+0x2ca/0x43c0 kernel/sched/core.c:6292
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
freezable_schedule include/linux/freezer.h:172 [inline]
do_nanosleep+0x1f1/0x770 kernel/time/hrtimer.c:2026
hrtimer_nanosleep+0x33e/0x590 kernel/time/hrtimer.c:2079
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1314 [inline]
__se_sys_clock_nanosleep+0x30b/0x3a0 kernel/time/posix-timers.c:1291
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fe6afdb4ed7
Code: 48 89 fa 4c 89 df e8 a8 56 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffc6c480530 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 0000555574843500 RCX: 00007fe6afdb4ed7
RDX: 00007ffc6c480570 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffc6c480a50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004
R13: 00007ffc6c4805ac R14: 00007ffc6c480640 R15: 0000000000000000