INFO: task syz.0.17:5954 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D stack:27320 pid:5954 ppid:5904 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x673/0xc80 kernel/locking/mutex.c:747
blkdev_put+0x100/0x7a0 block/bdev.c:944
blkdev_release+0x84/0x90 block/fops.c:604
__fput+0x221/0x930 fs/file_table.c:384
task_work_run+0x1d4/0x260 kernel/task_work.c:245
get_signal+0x11da/0x1390 kernel/signal.c:2679
arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/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:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f5d0f19ce59
RSP: 002b:00007f5d1014d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f5d0f415fa0 RCX: 00007f5d0f19ce59
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007f5d0f232e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5d0f416038 R14: 00007f5d0f415fa0 R15: 00007fff79d14048
Showing all locks held in the system:
1 lock held by khungtaskd/29:
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
5 locks held by kworker/u4:11/3512:
#0: ffff8880b8f3c298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559
#1: ffff8880b8f28a00 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline]
#1: ffff8880b8f28a00 (psi_seq){-.-.}-{0:0}, at: __schedule+0x21d3/0x4660 kernel/sched/core.c:6695
#2: ffff8880b8f295d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999
#3: ffffffff9756ee50 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x6c/0x500 lib/debugobjects.c:709
#4: ffffffff8cfe1dc8 (text_mutex){+.+.}-{3:3}, at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145
2 locks held by getty/5526:
#0: ffff88802d1f60a0 (&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+0x428/0x1370 drivers/tty/n_tty.c:2217
1 lock held by udevd/5916:
#0: ffff8880223434c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x11b/0x610 block/bdev.c:805
1 lock held by udevd/5917:
#0: ffff8880222234c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x11b/0x610 block/bdev.c:805
1 lock held by udevd/5918:
#0: ffff888141bf04c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x11b/0x610 block/bdev.c:805
1 lock held by udevd/5919:
#0: ffff888141f484c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x11b/0x610 block/bdev.c:805
1 lock held by syz.0.17/5954:
#0: ffff8880222234c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x100/0x7a0 block/bdev.c:944
1 lock held by syz.1.33/6000:
#0: ffff888141bf04c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x100/0x7a0 block/bdev.c:944
1 lock held by syz.2.88/6135:
#0: ffff8880223434c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x100/0x7a0 block/bdev.c:944
1 lock held by udevd/6173:
#0: ffff8880223534c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x11b/0x610 block/bdev.c:805
1 lock held by syz.3.108/6194:
#0: ffff888141f484c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x100/0x7a0 block/bdev.c:944
1 lock held by syz.4.116/6234:
#0: ffff8880223534c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x100/0x7a0 block/bdev.c:944
=============================================
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 05/09/2026
Call Trace:
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 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+0xf59/0xfa0 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: 3512 Comm: kworker/u4:11 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:find_stack lib/stackdepot.c:349 [inline]
RIP: 0010:__stack_depot_save+0x14b/0x660 lib/stackdepot.c:390
Code: c1 c6 04 29 f2 31 d1 c1 c2 0e 29 d1 41 31 cc c1 c1 18 41 29 cc 4c 8b 2d 8b 75 01 13 8b 2d 81 75 01 13 44 21 e5 4d 8b 7c ed 00 <4d> 85 ff 74 31 89 c1 eb 08 4d 8b 3f 4d 85 ff 74 25 45 39 67 08 75
RSP: 0018:ffffc9000ce97768 EFLAGS: 00000202
RAX: 000000000000000b RBX: ffffc9000ce977c0 RCX: 0000000004a81d47
RDX: 000000005b6403a5 RSI: 000000007201d7f6 RDI: 0000000000000001
RBP: 0000000000053d34 R08: 0000000000082820 R09: 0000000030c9ac0a
R10: 000000006f740ffd R11: 0000000000000000 R12: 00000000ca953d34
R13: ffff88823b400000 R14: 0000000000000001 R15: ffff88802f6c7e50
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30363fff CR3: 000000000cf32000 CR4: 00000000003506f0
Call Trace:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_set_track+0x5f/0x70 mm/kasan/common.c:53
____kasan_kmalloc mm/kasan/common.c:375 [inline]
__kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384
kasan_kmalloc include/linux/kasan.h:198 [inline]
__do_kmalloc_node mm/slab_common.c:1007 [inline]
__kmalloc_node_track_caller+0xb4/0x230 mm/slab_common.c:1027
kmalloc_reserve+0x116/0x240 net/core/skbuff.c:584
__alloc_skb+0x138/0x2c0 net/core/skbuff.c:653
alloc_skb include/linux/skbuff.h:1316 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
nsim_dev_trap_report_work+0x253/0xa90 drivers/net/netdevsim/dev.c:851
process_one_work kernel/workqueue.c:2653 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2730
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2811
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