INFO: task syz.0.16:4427 blocked for more than 143 seconds.
Not tainted 6.1.144-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.16 state:D stack:27336 pid:4427 ppid:4363 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x555/0xaf0 kernel/locking/mutex.c:747
blkdev_put+0xfe/0x710 block/bdev.c:913
blkdev_close+0x51/0x80 block/fops.c:514
__fput+0x22c/0x920 fs/file_table.c:320
task_work_run+0x1ca/0x250 kernel/task_work.c:203
get_signal+0x11a6/0x1350 kernel/signal.c:2648
arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb372f8e929
RSP: 002b:00007fb373e75038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007fb3731b5fa0 RCX: 00007fb372f8e929
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007fb373010b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb3731b5fa0 R15: 00007ffd5cd85ba8
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2b730 (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: ffffffff8cb2bf50 (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/28:
#0: ffffffff8cb2ada0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2ada0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2ada0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
1 lock held by klogd/3626:
#0: ffff8880b8f3aa98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
2 locks held by getty/4023:
#0: ffff888030064098 (&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
1 lock held by udevd/4272:
#0: ffff8881443c94c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x13d/0xa60 block/bdev.c:815
1 lock held by udevd/4274:
#0: ffff8880249134c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x13d/0xa60 block/bdev.c:815
2 locks held by kworker/u5:1/4326:
#0: ffff888024a19938 ((wq_completion)nbd3-recv){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90003337d00 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
1 lock held by udevd/4370:
#0: ffff8880249fb4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x13d/0xa60 block/bdev.c:815
5 locks held by kworker/u4:6/4398:
#0: ffff8880b8f3aa98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
#1: ffff88807e0e6358 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0x5c/0x1080 kernel/sched/core.c:4111
#2: ffffffff8cb2ada0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#2: ffffffff8cb2ada0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#2: ffffffff8cb2ada0 (rcu_read_lock){....}-{1:2}, at: batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
#2: ffffffff8cb2ada0 (rcu_read_lock){....}-{1:2}, at: batadv_nc_worker+0xce/0x600 net/batman-adv/network-coding.c:719
#3: ffffffff96e142d8 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x6a/0x490 lib/debugobjects.c:698
#4: ffffe8ffffd83a88 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x164/0x6d0 kernel/sched/psi.c:949
1 lock held by syz.0.16/4427:
#0: ffff8881443c94c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfe/0x710 block/bdev.c:913
1 lock held by syz.1.60/4540:
#0: ffff8880249134c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfe/0x710 block/bdev.c:913
1 lock held by udevd/4563:
#0: ffff888024a204c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x13d/0xa60 block/bdev.c:815
1 lock held by syz.2.64/4567:
#0: ffff8880249fb4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfe/0x710 block/bdev.c:913
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.144-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
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
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3619 Comm: syslogd Not tainted 6.1.144-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__bfs kernel/locking/lockdep.c:1735 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1842 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2782 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3094 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3209 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3825 [inline]
RIP: 0010:__lock_acquire+0x3041/0x7c50 kernel/locking/lockdep.c:5049
Code: 28 50 11 ff c0 25 ff 0f 00 00 89 05 79 28 50 11 48 85 db 0f 84 a6 05 00 00 4c 8d 73 10 4d 89 f5 49 c1 ed 03 41 80 7c 15 00 00 <74> 12 4c 89 f7 e8 55 33 6f 00 48 ba 00 00 00 00 00 fc ff df 4d 8b
RSP: 0018:ffffc900032a7400 EFLAGS: 00000046
RAX: ffffffff933e66b8 RBX: ffffffff933e66b8 RCX: 00000000000001d9
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff9047a590
RBP: ffffc900032a7650 R08: dffffc0000000000 R09: ffffc900032a75a0
R10: fffff52000654ebb R11: 1ffff92000654eb4 R12: ffff88807d9f8b78
R13: 1ffffffff267ccd9 R14: ffffffff933e66c8 R15: ffffffff9048d0cc
FS: 00007fd79049cc80(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555682d1808 CR3: 000000001821e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
_raw_spin_lock_nested+0x2e/0x40 kernel/locking/spinlock.c:378
raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
raw_spin_rq_lock kernel/sched/sched.h:1355 [inline]
rq_lock kernel/sched/sched.h:1645 [inline]
ttwu_queue kernel/sched/core.c:3902 [inline]
try_to_wake_up+0x4ec/0x1080 kernel/sched/core.c:4227
autoremove_wake_function+0x13/0xf0 kernel/sched/wait.c:419
__wake_up_common+0x2a4/0x4e0 kernel/sched/wait.c:107
__wake_up_common_lock kernel/sched/wait.c:138 [inline]
__wake_up_sync_key+0x10d/0x180 kernel/sched/wait.c:208
__unix_dgram_recvmsg+0x498/0xd70 net/unix/af_unix.c:2478
sock_recvmsg_nosec net/socket.c:1022 [inline]
sock_recvmsg net/socket.c:1040 [inline]
sock_read_iter+0x2bf/0x370 net/socket.c:1121
call_read_iter include/linux/fs.h:2259 [inline]
new_sync_read fs/read_write.c:389 [inline]
vfs_read+0x434/0x920 fs/read_write.c:470
ksys_read+0x143/0x240 fs/read_write.c:613
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd7905ec407
Code: 48 89 fa 4c 89 df e8 38 aa 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:00007ffd0cad70c0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fd79049cc80 RCX: 00007fd7905ec407
RDX: 00000000000000ff RSI: 00005642cb492950 RDI: 0000000000000000
RBP: 00005642cb492910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005642cb492982
R13: 0000000000000000 R14: 00005642cb492950 R15: 00005642a4fd3d98