INFO: task syz.5.196:7187 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.196 state:D stack:27312 pid:7187 ppid:6741 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_get_by_dev+0x121/0x600 block/bdev.c:805
swsusp_check+0x5b/0x390 kernel/power/swap.c:1525
software_resume+0x4d/0x2e0 kernel/power/hibernate.c:958
resume_store+0x2f2/0x450 kernel/power/hibernate.c:1216
kernfs_fop_write_iter+0x3b6/0x520 fs/kernfs/file.c:352
call_write_iter include/linux/fs.h:2018 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x43b/0x940 fs/read_write.c:584
ksys_write+0x147/0x250 fs/read_write.c:637
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: 0033:0x7f1fb438f749
RSP: 002b:00007f1fb25f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f1fb45e6090 RCX: 00007f1fb438f749
RDX: 0000000000000012 RSI: 0000200000000000 RDI: 0000000000000003
RBP: 00007f1fb4413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1fb45e6128 R14: 00007f1fb45e6090 R15: 00007fff1c2e0808
Showing all locks held in the system:
3 locks held by kworker/1:1/28:
#0: ffff8880192f7138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff8880192f7138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc90000a4fd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90000a4fd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffff888142b00190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:995 [inline]
#2: ffff888142b00190 (&dev->mutex){....}-{3:3}, at: hub_event+0x185/0x49c0 drivers/usb/core/hub.c:5861
1 lock held by khungtaskd/29:
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}
, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
4 locks held by kworker/u4:2/42:
#0: ffff8880b8e3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:566
#1: ffff8880b8f289c0 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline]
#1: ffff8880b8f289c0 (psi_seq){-.-.}-{0:0}, at: __schedule+0x20ee/0x44d0 kernel/sched/core.c:6694
#2: ffff8880b8f29598 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x73b/0xdb0 kernel/time/timer.c:1112
#3: ffffffff9707b5f8 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x6c/0x4b0 lib/debugobjects.c:709
2 locks held by kworker/1:2/787:
#0: ffff8880b8e3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:566
#1: ffff8880b8f289c0 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline]
#1: ffff8880b8f289c0 (psi_seq){-.-.}-{0:0}, at: __schedule+0x20ee/0x44d0 kernel/sched/core.c:6694
2 locks held by kworker/u4:7/1344:
3 locks held by kworker/u4:10/3448:
#0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc9000d3d7d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc9000d3d7d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffffffff8cd357c0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:4089
2 locks held by getty/5525:
#0: ffff88814c94f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000328b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
1 lock held by udevd/5755:
#0: ffff8880220954c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
4 locks held by udevd/5866:
#0: ffff88805f1c88b8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xb1/0xd50 fs/seq_file.c:182
#1: ffff88802f35d488 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x5c/0x410 fs/kernfs/file.c:172
#2: ffff888044504008 (kn->active#24){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888044504008 (kn->active#24){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x410 fs/kernfs/file.c:173
#3: ffff88807d9040a8 (&ep->wq){....}-{2:2}, at: __wake_up_common_lock kernel/sched/wait.c:137 [inline]
#3: ffff88807d9040a8 (&ep->wq){....}-{2:2}, at: __wake_up_sync_key kernel/sched/wait.c:213 [inline]
#3: ffff88807d9040a8 (&ep->wq){....}-{2:2}, at: __wake_up_sync+0xef/0x180 kernel/sched/wait.c:245
1 lock held by udevd/5929:
1 lock held by dhcpcd/6262:
#0: ffff88801fe7c420 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#0: ffff88801fe7c420 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
#0: ffff88801fe7c420 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x9b/0x230 net/socket.c:1421
6 locks held by syz.5.196/7187:
#0: ffff888064a2e5c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040
#1: ffff88802cc4e418 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x20e/0x940 fs/read_write.c:580
#2: ffff88805e9fc488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x520 fs/kernfs/file.c:343
#3: ffff88801ce525d8 (kn->active#67){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#3: ffff88801ce525d8 (kn->active#67){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x23a/0x520 fs/kernfs/file.c:344
#4: ffffffff8cbe3988 (system_transition_mutex){+.+.}-{3:3}, at: software_resume+0x43/0x2e0 kernel/power/hibernate.c:957
#5: ffff8880220954c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
1 lock held by syz.6.271/7718:
#0: ffff8880220954c8 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1af/0x330 block/bdev.c:1076
5 locks held by syz.8.478/8934:
#0: ffff88802fa600c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040
#1: ffff88802cc4e418 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x20e/0x940 fs/read_write.c:580
#2: ffff88805e713088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x520 fs/kernfs/file.c:343
#3: ffff88801ce525d8 (kn->active#67){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#3: ffff88801ce525d8 (kn->active#67){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x23a/0x520 fs/kernfs/file.c:344
#4: ffffffff8cbe3988 (system_transition_mutex){+.+.}-{3:3}, at: lock_system_sleep+0x49/0x70 kernel/power/main.c:56
1 lock held by syz-executor/9146:
#0: ffffffff8cd358f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
#0: ffffffff8cd358f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x448/0x830 kernel/rcu/tree_exp.h:1004
1 lock held by syz.2.610/9776:
#0: ffffffff8cd357c0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:4089
4 locks held by dhcpcd-run-hook/9819:
=============================================
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: 0 Comm: swapper/0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:148
Code: cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d 23 bb 40 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 66 0f 1f 00 55 41 57 41 56
RSP: 0018:ffffffff8ca07d80 EFLAGS: 000002c2
RAX: 9aab9dd482305200 RBX: ffffffff8161881b RCX: 9aab9dd482305200
RDX: 0000000000000001 RSI: ffffffff8aaabce0 RDI: ffffffff8afc6f80
RBP: ffffffff8ca07eb8 R08: ffff8880b8e36b2b R09: 1ffff110171c6d65
R10: dffffc0000000000 R11: ffffed10171c6d66 R12: ffffffff8e4a2128
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1952688
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005624bdd5c950 CR3: 000000002dd64000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:753
default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97
cpuidle_idle_call kernel/sched/idle.c:170 [inline]
do_idle+0x1eb/0x510 kernel/sched/idle.c:282
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380
rest_init+0x2e2/0x300 init/main.c:744
arch_call_rest_init+0xe/0x10 init/main.c:841
start_kernel+0x459/0x4e0 init/main.c:1086
x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555
x86_64_start_kernel+0x60/0x60 arch/x86/kernel/head64.c:536
secondary_startup_64_no_verify+0x179/0x17b