INFO: task syz-executor.0:6215 blocked for more than 143 seconds.
Not tainted 6.16.0-rc6-syzkaller-gf4a40a4282f4 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0 state:D stack:27544 pid:6215 tgid:6214 ppid:6156 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6879
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common+0x2ff/0x4e0 kernel/sched/completion.c:116
__flush_workqueue+0x3e2/0x1230 kernel/workqueue.c:4002
nbd_start_device_ioctl drivers/block/nbd.c:1541 [inline]
__nbd_ioctl drivers/block/nbd.c:1602 [inline]
nbd_ioctl+0x300/0xda0 drivers/block/nbd.c:1642
blkdev_ioctl+0x277/0x6d0 block/ioctl.c:704
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl fs/ioctl.c:893 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893
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: 0033:0x7fd63807cb29
RSP: 002b:00007fd638e640c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fd63819bf80 RCX: 00007fd63807cb29
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007fd6380c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fd63819bf80 R15: 00007ffdd6ebc748
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770
2 locks held by kworker/u9:0/50:
#0: ffff88802676b148 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc90000ba7d10 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
2 locks held by getty/5587:
#0: ffff88803272c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
3 locks held by syz-executor.0/10342:
#0: ffff888026627230 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x150/0xda0 drivers/block/nbd.c:1635
#1: ffff888142f1d8b0 (&q->q_usage_counter(io)#49){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 block/blk-mq.c:205
#2: ffff888142f1d8e8 (&q->q_usage_counter(queue)){+.+.}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 block/blk-mq.c:205
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-syzkaller-gf4a40a4282f4 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xf70/0x12c0 kernel/hung_task.c:470
kthread+0x3c5/0x780 kernel/kthread.c:464
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: 6529 Comm: syz-executor.0 Not tainted 6.16.0-rc6-syzkaller-gf4a40a4282f4 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x2c/0xc0 kernel/rcu/tree.c:745
Code: 1e fa 55 53 65 ff 05 43 96 2e 12 e8 1e 1b e5 09 48 c7 c3 28 32 d1 93 89 c5 83 f8 07 0f 87 82 00 00 00 48 8d 3c ed a0 dd f3 8d <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75
RSP: 0018:ffffc90004ed7bc0 EFLAGS: 00000297
RAX: 0000000000000001 RBX: ffffffff93d13228 RCX: ffffffff817c90d5
RDX: ffff88805d8a2440 RSI: ffffffff8c1573e0 RDI: ffffffff8df3dda8
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff817c9167
R13: ffff88805d8a2440 R14: 0000000000000000 R15: ffff88803233a1d0
FS: 00005555565e4480(0000) GS:ffff888124820000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2a236abc98 CR3: 000000007ef87000 CR4: 00000000003526f0
Call Trace:
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0x201/0x2f0 kernel/locking/lockdep.c:5882
__raw_read_unlock include/linux/rwlock_api_smp.h:231 [inline]
_raw_read_unlock+0x16/0x50 kernel/locking/spinlock.c:260
__do_wait+0x397/0x890 kernel/exit.c:1687
do_wait+0x21e/0x5a0 kernel/exit.c:1709
kernel_wait4+0x16b/0x280 kernel/exit.c:1868
__do_sys_wait4+0x15d/0x170 kernel/exit.c:1896
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: 0033:0x7f2a22879557
Code: 89 7c 24 10 48 89 4c 24 18 e8 d5 a3 02 00 4c 8b 54 24 18 8b 54 24 14 41 89 c0 48 8b 74 24 08 8b 7c 24 10 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 89 44 24 10 e8 25 a4 02 00 8b 44
RSP: 002b:00007ffd3caaab20 EFLAGS: 00000293 ORIG_RAX: 000000000000003d
RAX: ffffffffffffffda RBX: 0000000000000ec4 RCX: 00007f2a22879557
RDX: 0000000040000001 RSI: 00007ffd3caaabac RDI: 00000000ffffffff
RBP: 00007ffd3caaabac R08: 0000000000000000 R09: 00007f2a236ad000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032
R13: 000000000003c65a R14: 000000000003c655 R15: 0000000000000003