INFO: task syz.2.4956:25589 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.4956      state:D stack:25512 pid:25589 tgid:25586 ppid:5814   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: 0033:0x7fa9edb9c799
RSP: 002b:00007fa9eeaa7028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fa9ede15fa0 RCX: 00007fa9edb9c799
RDX: 0000000000040800 RSI: 0000200000000400 RDI: 0000000000000006
RBP: 00007fa9edc32c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa9ede16038 R14: 00007fa9ede15fa0 R15: 00007ffcca71f0d8
 </TASK>
INFO: task syz.0.4959:25594 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.4959      state:D stack:28008 pid:25594 tgid:25593 ppid:5812   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: 0033:0x7f9a3355cfce
RSP: 002b:00007f9a344dfe88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f9a344e16c0 RCX: 00007f9a3355cfce
RDX: 0000000000000020 RSI: 00007f9a344e0000 RDI: 0000000000000006
RBP: 0000000000000000 R08: 00007f9a344dff04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 00007f9a344dff58 R14: 00007f9a344e0000 R15: 0000000000000000
 </TASK>
INFO: task syz.0.4959:25597 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.4959      state:D stack:28160 pid:25597 tgid:25593 ppid:5812   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: 0033:0x7f9a3355cfce
RSP: 002b:00007f9a344bee88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f9a344c06c0 RCX: 00007f9a3355cfce
RDX: 0000000000000024 RSI: 00007f9a344bf000 RDI: 0000000000000006
RBP: 0000000000000000 R08: 00007f9a344bef04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 00007f9a344bef58 R14: 00007f9a344bf000 R15: 0000000000000000
 </TASK>
INFO: task syz.1.4963:25609 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.4963      state:D stack:27144 pid:25609 tgid:25608 ppid:5808   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: 0033:0x7f91f0b9c799
RSP: 002b:00007f91f1b08028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f91f0e15fa0 RCX: 00007f91f0b9c799
RDX: 0000000000000000 RSI: 0000200000000100 RDI: 0000000000000004
RBP: 00007f91f0c32c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f91f0e16038 R14: 00007f91f0e15fa0 R15: 00007ffea9b86408
 </TASK>
INFO: task syz-executor:25626 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:23400 pid:25626 tgid:25626 ppid:1      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: 0033:0x7fa8d175cfce
RSP: 002b:00007ffe65e261c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055557e66f500 RCX: 00007fa8d175cfce
RDX: 0000000000000020 RSI: 00007fa8d2544670 RDI: 0000000000000005
RBP: 0000000000000001 R08: 00007ffe65e26244 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005
R13: 00007ffe65e26298 R14: 00007fa8d2544670 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:25628 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22784 pid:25628 tgid:25628 ppid:1      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: 0033:0x7f909c95cfce
RSP: 002b:00007ffde04b6d28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00005555886af500 RCX: 00007f909c95cfce
RDX: 0000000000000020 RSI: 00007f909d744670 RDI: 0000000000000005
RBP: 0000000000000001 R08: 00007ffde04b6da4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005
R13: 00007ffde04b6df8 R14: 00007f909d744670 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:25644 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22856 pid:25644 tgid:25644 ppid:1      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: 0033:0x7f387675cfce
RSP: 002b:00007fff98f73a98 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055556cfee500 RCX: 00007f387675cfce
RDX: 0000000000000020 RSI: 00007f3877544670 RDI: 0000000000000005
RBP: 0000000000000001 R08: 00007fff98f73b14 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005
R13: 00007fff98f73b68 R14: 00007f3877544670 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e75e520 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5637:
 #0: ffff88810b3010a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
1 lock held by udevd/19077:
 #0: ffff888109159358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by udevd/19732:
 #0: ffff888109b15358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by udevd/19759:
 #0: ffff888107729358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
6 locks held by syz.2.4956/25589:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
 #2: ffff888109b06a78 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_genl_reconfigure+0x4c1/0x1ea0
 #3: ffff888109b0b668 (&q->limits_lock){+.+.}-{4:4}, at: nbd_set_size+0x263/0x680
 #4: ffff888109b0b008 (&q->q_usage_counter(io)#51){++++}-{0:0}, at: queue_limits_commit_update_frozen+0x55/0xd0
 #5: ffff888109b0b040 (&q->q_usage_counter(queue)#35){+.+.}-{0:0}, at: queue_limits_commit_update_frozen+0x55/0xd0
2 locks held by syz.0.4959/25594:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz.0.4959/25597:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz.1.4963/25609:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/25626:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/25628:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/25644:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/25658:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/25667:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/25676:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/25686:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/25695:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/25704:
 #0: ffffffff8fc3b930 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8fc3b748 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 35 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 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: 8e 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 f2 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:ffffffff8e407dc0 EFLAGS: 00000202
RAX: 000000000048040b RBX: ffffffff819a900a RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8def76c1 RDI: ffffffff8c27c200
RBP: ffffffff8e407eb0 R08: ffff88812103395b R09: 1ffff1102420672b
R10: dffffc0000000000 R11: ffffed102420672c R12: 0000000000000000
R13: 1ffffffff1c929d8 R14: 0000000000000000 R15: 1ffffffff1c929d8
FS:  0000000000000000(0000) GS:ffff88818de5d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8e2e287e20 CR3: 000000016dc90000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 default_idle+0x9/0x20
 default_idle_call+0x72/0xb0
 do_idle+0x36a/0x5f0
 cpu_startup_entry+0x43/0x60
 rest_init+0x2de/0x300
 start_kernel+0x385/0x3d0
 x86_64_start_reservations+0x24/0x30
 x86_64_start_kernel+0x143/0x1c0
 common_startup_64+0x13e/0x147
 </TASK>
