INFO: task syz.0.2405:15261 blocked for more than 143 seconds.
Not tainted 6.16.0-syzkaller-11852-g479058002c32 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2405 state:D
stack:25384 pid:15261 tgid:15261 ppid:5842 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x82a/0x10b0 kernel/locking/mutex.c:760
bdev_release+0x15a/0x6d0 block/bdev.c:1128
blkdev_release+0x15/0x20 block/fops.c:699
__fput+0x402/0xb70 fs/file_table.c:468
task_work_run+0x150/0x240 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xeb/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa44d98ebe9
RSP: 002b:00007ffe4da78088 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007fa44dbb7da0 RCX: 00007fa44d98ebe9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fa44dbb7da0 R08: 00000000000000a4 R09: 000000094da7837f
R10: 00007fa44dbb7cb0 R11: 0000000000000246 R12: 00000000000c442f
R13: 00007ffe4da78180 R14: ffffffffffffffff R15: 00007ffe4da781a0
INFO: task syz.0.2405:15262 blocked for more than 143 seconds.
Not tainted 6.16.0-syzkaller-11852-g479058002c32 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2405 state:D stack:27224 pid:15262 tgid:15261 ppid:5842 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x82a/0x10b0 kernel/locking/mutex.c:760
nbd_start_device_ioctl drivers/block/nbd.c:1552 [inline]
__nbd_ioctl drivers/block/nbd.c:1612 [inline]
nbd_ioctl+0x30a/0xda0 drivers/block/nbd.c:1652
blkdev_ioctl+0x274/0x6d0 block/ioctl.c:705
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:598 [inline]
__se_sys_ioctl fs/ioctl.c:584 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:584
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa44d98ebe9
RSP: 002b:00007fa44e7d1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa44dbb5fa0 RCX: 00007fa44d98ebe9
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000005
RBP: 00007fa44da11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa44dbb6038 R14: 00007fa44dbb5fa0 R15: 00007ffe4da77f28
INFO: task syz.0.2405:15263 blocked for more than 143 seconds.
Not tainted 6.16.0-syzkaller-11852-g479058002c32 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2405 state:D stack:28296 pid:15263 tgid:15261 ppid:5842 task_flags:0x480140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
blk_mq_freeze_queue_wait+0x143/0x1b0 block/blk-mq.c:190
blk_mq_freeze_queue include/linux/blk-mq.h:934 [inline]
queue_limits_commit_update_frozen+0x93/0x110 block/blk-settings.c:535
nbd_set_size+0x4da/0x720 drivers/block/nbd.c:374
__nbd_ioctl drivers/block/nbd.c:1603 [inline]
nbd_ioctl+0xd34/0xda0 drivers/block/nbd.c:1652
blkdev_ioctl+0x274/0x6d0 block/ioctl.c:705
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:598 [inline]
__se_sys_ioctl fs/ioctl.c:584 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:584
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa44d98ebe9
RSP: 002b:00007fa44e7b0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa44dbb6090 RCX: 00007fa44d98ebe9
RDX: 000000000000c0d8 RSI: 000000000000ab07 RDI: 0000000000000005
RBP: 00007fa44da11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa44dbb6128 R14: 00007fa44dbb6090 R15: 00007ffe4da77f28
INFO: task syz.4.2412:15284 blocked for more than 144 seconds.
Not tainted 6.16.0-syzkaller-11852-g479058002c32 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.2412 state:D stack:27096 pid:15284 tgid:15281 ppid:5849 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x82a/0x10b0 kernel/locking/mutex.c:760
sync_bdevs+0xfd/0x360 block/bdev.c:1288
ksys_sync+0xb2/0x150 fs/sync.c:105
__do_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f766658ebe9
RSP: 002b:00007f76673ee038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f76667b5fa0 RCX: 00007f766658ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f76667b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f76667b6038 R14: 00007f76667b5fa0 R15: 00007ffdee99af38
Showing all locks held in the system:
1 lock held by rcu_preempt/16:
#0: ffff8880b843a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:644 [inline]
#0: ffff8880b843a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:629
1 lock held by khungtaskd/31:
#0: ffffffff8e5c1160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c1160 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c1160 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by getty/5603:
#0: ffff88814dd360a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
5 locks held by kworker/u8:12/6732:
1 lock held by udevd/11726:
#0: ffff888143bb0358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945
1 lock held by syz.0.2405/15261:
#0: ffff888143bb0358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x15a/0x6d0 block/bdev.c:1128
1 lock held by syz.0.2405/15262:
#0: ffff888026867230 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_start_device_ioctl drivers/block/nbd.c:1552 [inline]
#0: ffff888026867230 (&nbd->config_lock){+.+.}-{4:4}, at: __nbd_ioctl drivers/block/nbd.c:1612 [inline]
#0: ffff888026867230 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x30a/0xda0 drivers/block/nbd.c:1652
4 locks held by syz.0.2405/15263:
#0: ffff888026867230 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x150/0xda0 drivers/block/nbd.c:1645
#1: ffff888143b3c1e8 (&q->limits_lock){+.+.}-{4:4}, at: queue_limits_start_update include/linux/blkdev.h:1066 [inline]
#1: ffff888143b3c1e8 (&q->limits_lock){+.+.}-{4:4}, at: nbd_set_size+0x2b6/0x720 drivers/block/nbd.c:354
#2: ffff888143b3bb88 (&q->q_usage_counter(io)#49){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 block/blk-mq.c:205
#3: ffff888143b3bbc0 (&q->q_usage_counter(queue)){+.+.}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 block/blk-mq.c:205
1 lock held by syz.4.2412/15284:
#0: ffff888143bb0358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0xfd/0x360 block/bdev.c:1288
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-syzkaller-11852-g479058002c32 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf0e/0x1260 kernel/hung_task.c:491
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-syzkaller-11852-g479058002c32 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 4c 63 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d f3 82 17 00 fb f4 4c 0d 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df8 EFLAGS: 000002c2
RAX: 0000000004244967 RBX: 0000000000000001 RCX: ffffffff8b928c29
RDX: 0000000000000000 RSI: ffffffff8de4d731 RDI: ffffffff8c161100
RBP: ffffed1003c56488 R08: 0000000000000001 R09: ffffed10170a6655
R10: ffff8880b85332ab R11: 0000000000000000 R12: 0000000000000001
R13: ffff88801e2b2440 R14: ffffffff90aaf390 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881247c6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc9a33cc18 CR3: 000000006aa60000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 000000000000508c
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x391/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428
start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x148