INFO: task syz.0.11360:15790 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.11360     state:D stack:26240 pid:15790 tgid:15789 ppid:5809   task_flags:0x480140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 blk_mq_freeze_queue_wait+0x101/0x180
 queue_limits_commit_update_frozen+0x55/0xd0
 nbd_set_size+0x454/0x680
 nbd_genl_reconfigure+0x7f5/0x1ea0
 genl_family_rcv_msg_doit+0x22a/0x330
 genl_rcv_msg+0x61c/0x7a0
 netlink_rcv_skb+0x232/0x4b0
 genl_rcv+0x28/0x40
 netlink_unicast+0x80f/0x9b0
 netlink_sendmsg+0x813/0xb40
 ____sys_sendmsg+0x972/0x9f0
 ___sys_sendmsg+0x2a5/0x360
 __x64_sys_sendmsg+0x1bd/0x2a0
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7effa239c799
RSP: 002b:00007effa325d028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007effa2615fa0 RCX: 00007effa239c799
RDX: 0000000000048040 RSI: 00002000000000c0 RDI: 000000000000000a
RBP: 00007effa2432c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007effa2616038 R14: 00007effa2615fa0 R15: 00007fff853b9038
 </TASK>
INFO: task syz.0.11360:15791 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.11360     state:D stack:28016 pid:15791 tgid:15789 ppid:5809   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 genl_rcv_msg+0x10b/0x7a0
 netlink_rcv_skb+0x232/0x4b0
 genl_rcv+0x28/0x40
 netlink_unicast+0x80f/0x9b0
 netlink_sendmsg+0x813/0xb40
 ____sys_sendmsg+0x972/0x9f0
 ___sys_sendmsg+0x2a5/0x360
 __x64_sys_sendmsg+0x1bd/0x2a0
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7effa239c799
RSP: 002b:00007effa323c028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007effa2616090 RCX: 00007effa239c799
RDX: 0000000000048040 RSI: 00002000000000c0 RDI: 000000000000000a
RBP: 00007effa2432c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007effa2616128 R14: 00007effa2616090 R15: 00007fff853b9038
 </TASK>
INFO: task syz.0.11360:15795 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.11360     state:D stack:28576 pid:15795 tgid:15789 ppid:5809   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 genl_rcv_msg+0x10b/0x7a0
 netlink_rcv_skb+0x232/0x4b0
 genl_rcv+0x28/0x40
 netlink_unicast+0x80f/0x9b0
 netlink_sendmsg+0x813/0xb40
 __sys_sendto+0x672/0x710
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7effa235cfce
RSP: 002b:00007effa3219e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007effa321b6c0 RCX: 00007effa235cfce
RDX: 0000000000000024 RSI: 00007effa321a000 RDI: 000000000000000a
RBP: 0000000000000000 R08: 00007effa3219f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000a
R13: 00007effa3219f58 R14: 00007effa321a000 R15: 0000000000000000
 </TASK>
INFO: task syz.2.11361:15793 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.11361     state:D stack:26120 pid:15793 tgid:15792 ppid:5811   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 genl_rcv_msg+0x10b/0x7a0
 netlink_rcv_skb+0x232/0x4b0
 genl_rcv+0x28/0x40
 netlink_unicast+0x80f/0x9b0
 netlink_sendmsg+0x813/0xb40
 __sys_sendto+0x672/0x710
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2e6295cfce
RSP: 002b:00007f2e637dee88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f2e637e06c0 RCX: 00007f2e6295cfce
RDX: 0000000000000020 RSI: 00007f2e637df000 RDI: 0000000000000004
RBP: 0000000000000000 R08: 00007f2e637def04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 00007f2e637def58 R14: 00007f2e637df000 R15: 0000000000000000
 </TASK>
INFO: task syz.2.11361:15794 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.11361     state:D stack:28512 pid:15794 tgid:15792 ppid:5811   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 genl_rcv_msg+0x10b/0x7a0
 netlink_rcv_skb+0x232/0x4b0
 genl_rcv+0x28/0x40
 netlink_unicast+0x80f/0x9b0
 netlink_sendmsg+0x813/0xb40
 __sys_sendto+0x672/0x710
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2e6295cfce
RSP: 002b:00007f2e637bde88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f2e637bf6c0 RCX: 00007f2e6295cfce
RDX: 0000000000000020 RSI: 00007f2e637be000 RDI: 0000000000000005
RBP: 0000000000000000 R08: 00007f2e637bdf04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005
R13: 00007f2e637bdf58 R14: 00007f2e637be000 R15: 0000000000000000
 </TASK>
INFO: task syz.1.11366:15823 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.11366     state:D stack:28576 pid:15823 tgid:15822 ppid:5804   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 genl_rcv_msg+0x10b/0x7a0
 netlink_rcv_skb+0x232/0x4b0
 genl_rcv+0x28/0x40
 netlink_unicast+0x80f/0x9b0
 netlink_sendmsg+0x813/0xb40
 __sys_sendto+0x672/0x710
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4a96f5cfce
RSP: 002b:00007f4a97d90e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f4a97d926c0 RCX: 00007f4a96f5cfce
RDX: 0000000000000020 RSI: 00007f4a97d91000 RDI: 0000000000000008
RBP: 0000000000000000 R08: 00007f4a97d90f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
R13: 00007f4a97d90f58 R14: 00007f4a97d91000 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e75e520 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5636:
 #0: ffff88816c5760a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
1 lock held by udevd/13632:
 #0: ffff88810a00c358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
6 locks held by syz.0.11360/15790:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
 #2: ffff88811fe46a78 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_genl_reconfigure+0x4c1/0x1ea0
 #3: ffff88810b285c88 (&q->limits_lock){+.+.}-{4:4}, at: nbd_set_size+0x263/0x680
 #4: ffff88810b285628 (&q->q_usage_counter(io)#72){++++}-{0:0}, at: queue_limits_commit_update_frozen+0x55/0xd0
 #5: ffff88810b285660 (&q->q_usage_counter(queue)#55){+.+.}-{0:0}, at: queue_limits_commit_update_frozen+0x55/0xd0
2 locks held by syz.0.11360/15791:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz.0.11360/15795:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz.2.11361/15793:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz.2.11361/15794:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz.1.11366/15823:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15827:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15830:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15847:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15858:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15860:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15875:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15892:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15894:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15909:
 #0: ffffffff8fc3b970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b788 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0

=============================================

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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd9/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 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: 0 Comm: swapper/1 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
RIP: 0010:pv_native_safe_halt+0xf/0x20
Code: 5e 6c 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d e3 b2 1a 00 fb f4 <e9> fc e9 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 00000202
RAX: 0000000000595e91 RBX: ffffffff819a900a RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8def8027 RDI: ffffffff8c27c200
RBP: ffffc90000197f10 R08: ffff88823c63395b R09: 1ffff110478c672b
R10: dffffc0000000000 R11: ffffed10478c672c R12: 0000000000000001
R13: 1ffff1102c156000 R14: 0000000000000001 R15: 1ffff1102c156000
FS:  0000000000000000(0000) GS:ffff8882a945c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f60847ff0e0 CR3: 0000000172fcc000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 default_idle+0x9/0x20
 default_idle_call+0x72/0xb0
 do_idle+0x36a/0x5f0
 cpu_startup_entry+0x43/0x60
 start_secondary+0x101/0x110
 common_startup_64+0x13e/0x147
 </TASK>
