INFO: task udevd:5891 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:20008 pid:5891 tgid:5891 ppid:5197 task_flags:0x400140 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
io_schedule+0x80/0xd0 kernel/sched/core.c:7871
folio_wait_bit_common+0x6b0/0xb80 mm/filemap.c:1330
folio_put_wait_locked mm/filemap.c:1494 [inline]
do_read_cache_folio+0x1aa/0x590 mm/filemap.c:4006
read_mapping_folio include/linux/pagemap.h:999 [inline]
read_part_sector+0xb6/0x2b0 block/partitions/core.c:722
adfspart_check_POWERTEC+0x8c/0xf30 block/partitions/acorn.c:454
check_partition block/partitions/core.c:141 [inline]
blk_add_partitions block/partitions/core.c:589 [inline]
bdev_disk_changed+0x75f/0x14b0 block/partitions/core.c:693
blkdev_get_whole+0x380/0x510 block/bdev.c:748
bdev_open+0x31e/0xd30 block/bdev.c:957
blkdev_open+0x457/0x600 block/fops.c:701
do_dentry_open+0x953/0x13f0 fs/open.c:965
vfs_open+0x3b/0x340 fs/open.c:1097
do_open fs/namei.c:3975 [inline]
path_openat+0x2ee5/0x3830 fs/namei.c:4134
do_filp_open+0x1fa/0x410 fs/namei.c:4161
do_sys_openat2+0x121/0x1c0 fs/open.c:1437
do_sys_open fs/open.c:1452 [inline]
__do_sys_openat fs/open.c:1468 [inline]
__se_sys_openat fs/open.c:1463 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1463
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb1170a7407
RSP: 002b:00007ffd613fd3b0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb117805880 RCX: 00007fb1170a7407
RDX: 00000000000a0800 RSI: 0000557536ed6360 RDI: ffffffffffffff9c
RBP: 0000557536ed5910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000557536ee8e20
R13: 0000557536ee3190 R14: 0000000000000000 R15: 0000557536ee8e20
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/1:2/980:
#0: ffff88801a055948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88801a055948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc90003837ba0 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc90003837ba0 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffffffff8e66a2d8 (pool_lock#2){-.-.}-{2:2}, at: class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline]
#2: ffffffff8e66a2d8 (pool_lock#2){-.-.}-{2:2}, at: free_obj_work+0x101/0x4a0 lib/debugobjects.c:498
1 lock held by klogd/5186:
#0: ffff8880b883a018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:638
2 locks held by getty/5590:
#0: ffff88814d67e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/5891:
#0: ffff888024ca7358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
3 locks held by kworker/u8:24/14486:
#0: ffff88801aedf148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88801aedf148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9000472fba0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9000472fba0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffffffff8df42fc0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3820
1 lock held by syz.3.2793/16139:
#0: ffffffff8df42fc0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3820
1 lock held by syz.3.2793/16140:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16140 Comm: syz.3.2793 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:rcu_read_lock_sched_held+0xb1/0x100 kernel/rcu/update.c:127
Code: a1 09 85 c0 74 36 bb 01 00 00 00 48 c7 04 24 0e 36 e0 45 4b c7 04 3e 00 00 00 00 65 48 8b 05 16 61 c9 10 48 3b 44 24 50 75 3f <89> d8 48 8d 65 e8 5b 41 5e 41 5f 5d e9 7e c5 a4 09 cc 65 8b 05 06
RSP: 0018:ffffc9001c3cf9e0 EFLAGS: 00000246
RAX: 2c46b8d96b86a500 RBX: 0000000000000000 RCX: 2c46b8d96b86a500
RDX: ffff88806d701e40 RSI: ffffffff8d8f6906 RDI: ffffffff8bbf0760
RBP: ffffc9001c3cfa70 R08: ffffc9001c3cfc57 R09: 0000000000000000
R10: ffffc9001c3cfc20 R11: ffffffffa0206e94 R12: 1ffff1100dae0458
R13: ffffc9001b727048 R14: 1ffff92003879f3c R15: dffffc0000000000
FS: 00007fc5966776c0(0000) GS:ffff888126138000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000b66030 CR3: 000000002776e000 CR4: 00000000003526f0
Call Trace:
task_cls_state+0x55/0x220 net/core/netclassid_cgroup.c:23
__task_get_classid include/net/cls_cgroup.h:50 [inline]
____bpf_get_cgroup_classid_curr net/core/filter.c:3099 [inline]
bpf_get_cgroup_classid_curr+0x18/0x60 net/core/filter.c:3097
bpf_prog_0f0c8c0b3aa622c6+0x23/0x29
bpf_dispatcher_nop_func include/linux/bpf.h:1350 [inline]
__bpf_prog_run include/linux/filter.h:721 [inline]
bpf_prog_run include/linux/filter.h:728 [inline]
bpf_prog_run_pin_on_cpu include/linux/filter.h:745 [inline]
bpf_flow_dissect+0x225/0x720 net/core/flow_dissector.c:1024
bpf_prog_test_run_flow_dissector+0x37c/0x5c0 net/bpf/test_run.c:1414
bpf_prog_test_run+0x2c7/0x340 kernel/bpf/syscall.c:4689
__sys_bpf+0x562/0x860 kernel/bpf/syscall.c:6168
__do_sys_bpf kernel/bpf/syscall.c:6260 [inline]
__se_sys_bpf kernel/bpf/syscall.c:6258 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6258
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc59578f6c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc596677038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fc5959e5fa0 RCX: 00007fc59578f6c9
RDX: 0000000000000050 RSI: 0000200000000600 RDI: 000000000000000a
RBP: 00007fc595811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc5959e6038 R14: 00007fc5959e5fa0 R15: 00007ffe6500ca88