INFO: task syz.1.5589:22729 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.5589      state:D stack:25352 pid:22729 tgid:22728 ppid:5851   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x9a/0x270
 wait_for_completion+0x2bf/0x5d0
 __flush_workqueue+0x6f7/0x14b0
 nbd_disconnect_and_put+0x9e/0x2a0
 nbd_genl_disconnect+0x485/0x570
 genl_family_rcv_msg_doit+0x215/0x300
 genl_rcv_msg+0x60e/0x790
 netlink_rcv_skb+0x208/0x470
 genl_rcv+0x28/0x40
 netlink_unicast+0x82f/0x9e0
 netlink_sendmsg+0x805/0xb30
 __sock_sendmsg+0x21c/0x270
 ____sys_sendmsg+0x505/0x830
 ___sys_sendmsg+0x21f/0x2a0
 __x64_sys_sendmsg+0x19b/0x260
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f745f98ebe9
RSP: 002b:00007f746071a038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f745fbb5fa0 RCX: 00007f745f98ebe9
RDX: 00000000000000c0 RSI: 0000200000000080 RDI: 0000000000000004
RBP: 00007f745fa11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f745fbb6038 R14: 00007f745fbb5fa0 R15: 00007fff10344508
 </TASK>
INFO: task syz.0.5590:22731 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.5590      state:D stack:26024 pid:22731 tgid:22730 ppid:5855   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 genl_rcv_msg+0x10d/0x790
 netlink_rcv_skb+0x208/0x470
 genl_rcv+0x28/0x40
 netlink_unicast+0x82f/0x9e0
 netlink_sendmsg+0x805/0xb30
 __sock_sendmsg+0x21c/0x270
 __sys_sendto+0x3bd/0x520
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9716d90a7c
RSP: 002b:00007f9717cabec0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f9717cabfc0 RCX: 00007f9716d90a7c
RDX: 0000000000000020 RSI: 00007f9717cac010 RDI: 0000000000000006
RBP: 0000000000000000 R08: 00007f9717cabf14 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000006
R13: 00007f9717cabf68 R14: 00007f9717cac010 R15: 0000000000000000
 </TASK>
INFO: task syz.2.5591:22736 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.5591      state:D stack:24584 pid:22736 tgid:22735 ppid:5847   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 genl_rcv_msg+0x10d/0x790
 netlink_rcv_skb+0x208/0x470
 genl_rcv+0x28/0x40
 netlink_unicast+0x82f/0x9e0
 netlink_sendmsg+0x805/0xb30
 __sock_sendmsg+0x21c/0x270
 __sys_sendto+0x3bd/0x520
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdd06390a7c
RSP: 002b:00007fdd07265ec0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fdd07265fc0 RCX: 00007fdd06390a7c
RDX: 0000000000000020 RSI: 00007fdd07266010 RDI: 0000000000000004
RBP: 0000000000000000 R08: 00007fdd07265f14 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000004
R13: 00007fdd07265f68 R14: 00007fdd07266010 R15: 0000000000000000
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 1094 Comm: kworker/u9:6 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:__mutex_lock+0xd4c/0x1350
Code: 65 8b 05 37 f0 24 07 85 c0 0f 84 56 03 00 00 bf 01 00 00 00 e8 55 8d 14 f6 65 8b 05 1e f0 24 07 31 db 85 c0 0f 84 45 03 00 00 <48> c7 84 24 c0 00 00 00 0e 36 e0 45 48 8b 84 24 b8 00 00 00 4a c7
RSP: 0018:ffffc900070477a0 EFLAGS: 00000286
RAX: 0000000080000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8be33660 RDI: 00000000ffffffff
RBP: ffffc90007047958 R08: ffffffff8fa38537 R09: 1ffffffff1f470a6
R10: dffffc0000000000 R11: fffffbfff1f470a7 R12: ffffffff8e1f2e80
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881a3c1a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a8b89a5e68 CR3: 000000000df36000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 static_key_disable_cpuslocked+0x8d/0x1b0
 static_key_disable+0x1a/0x20
 toggle_allocation_gate+0x1a1/0x240
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
