INFO: task syz.1.2604:15876 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.2604      state:D stack:25512 pid:15876 tgid:15875 ppid:5604   task_flags:0x480140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 blk_mq_freeze_queue_wait+0x101/0x180
 queue_limits_commit_update_frozen+0x55/0xd0
 nbd_set_size+0x454/0x680
 nbd_genl_reconfigure+0x7e9/0x1e80
 genl_family_rcv_msg_doit+0x233/0x340
 genl_rcv_msg+0x614/0x7a0
 netlink_rcv_skb+0x226/0x4a0
 genl_rcv+0x28/0x40
 netlink_unicast+0x7bb/0x940
 netlink_sendmsg+0x813/0xb40
 sock_sendmsg_nosec+0x13a/0x180
 ____sys_sendmsg+0x54e/0x850
 ___sys_sendmsg+0x2a5/0x360
 __x64_sys_sendmsg+0x1b1/0x290
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc64299de99
RSP: 002b:00007fc643790028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fc642c25fa0 RCX: 00007fc64299de99
RDX: 0000000000008080 RSI: 00002000000010c0 RDI: 0000000000000004
RBP: 00007fc642a33eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc642c26038 R14: 00007fc642c25fa0 R15: 00007ffdc90aa028
 </TASK>
INFO: task syz.2.2606:15883 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.2606      state:D stack:28480 pid:15883 tgid:15881 ppid:5611   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7bf/0x1550
 genl_rcv_msg+0x10b/0x7a0
 netlink_rcv_skb+0x226/0x4a0
 genl_rcv+0x28/0x40
 netlink_unicast+0x7bb/0x940
 netlink_sendmsg+0x813/0xb40
 sock_sendmsg_nosec+0x13a/0x180
 __sys_sendto+0x408/0x5a0
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fce9395e6ce
RSP: 002b:00007fce94809e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fce9480b6c0 RCX: 00007fce9395e6ce
RDX: 0000000000000024 RSI: 00007fce9480a000 RDI: 0000000000000004
RBP: 0000000000000000 R08: 00007fce94809f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 00007fce94809f58 R14: 00007fce9480a000 R15: 0000000000000000
 </TASK>
INFO: task syz.0.2607:15890 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2607      state:D stack:24992 pid:15890 tgid:15889 ppid:5608   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7bf/0x1550
 genl_rcv_msg+0x10b/0x7a0
 netlink_rcv_skb+0x226/0x4a0
 genl_rcv+0x28/0x40
 netlink_unicast+0x7bb/0x940
 netlink_sendmsg+0x813/0xb40
 sock_sendmsg_nosec+0x13a/0x180
 __sys_sendto+0x408/0x5a0
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb66655e6ce
RSP: 002b:00007fb6673c5e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fb6673c76c0 RCX: 00007fb66655e6ce
RDX: 0000000000000020 RSI: 00007fb6673c6000 RDI: 0000000000000008
RBP: 0000000000000000 R08: 00007fb6673c5f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
R13: 00007fb6673c5f58 R14: 00007fb6673c6000 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5432:
 #0: ffff888110e500a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034732e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360
7 locks held by kworker/0:7/10459:
1 lock held by udevd/14974:
 #0: ffff88810add4350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70
6 locks held by syz.1.2604/15876:
 #0: ffffffff9009dee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff9009dd20 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
 #2: ffff88810ae3ea60 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_genl_reconfigure+0x4bc/0x1e80
 #3: ffff88810ae43e78 (&q->limits_lock){+.+.}-{4:4}, at: nbd_set_size+0x263/0x680
 #4: ffff88810ae43840 (&q->q_usage_counter(io)#50){++++}-{0:0}, at: queue_limits_commit_update_frozen+0x55/0xd0
 #5: ffff88810ae43878 (&q->q_usage_counter(queue)#34){+.+.}-{0:0}, at: queue_limits_commit_update_frozen+0x55/0xd0
2 locks held by syz.2.2606/15883:
 #0: ffffffff9009dee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff9009dd20 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz.0.2607/15890:
 #0: ffffffff9009dee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff9009dd20 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15895:
 #0: ffffffff9009dee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff9009dd20 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15897:
 #0: ffffffff9009dee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff9009dd20 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15903:
 #0: ffffffff9009dee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff9009dd20 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15954:
 #0: ffffffff9009dee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff9009dd20 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15955:
 #0: ffffffff9009dee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff9009dd20 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/15957:
 #0: ffffffff9009dee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff9009dd20 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/16008:
 #0: ffffffff9009dee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff9009dd20 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/16010:
 #0: ffffffff9009dee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff9009dd20 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0
2 locks held by syz-executor/16013:
 #0: ffffffff9009dee8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff9009dd20 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0

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

NMI backtrace for cpu 1
CPU: 1 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/0x380
 sys_info+0x135/0x170
 watchdog+0xfd7/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 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: 10459 Comm: kworker/0:7 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_power_efficient neigh_periodic_work
RIP: 0010:check_preemption_disabled+0x0/0xe0
Code: c7 20 db 4b 8c 48 c7 c6 60 db 4b 8c eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <55> 41 57 41 56 53 65 8b 05 f7 dd 9b 07 65 8b 0d ec dd 9b 07 f7 c1
RSP: 0018:ffffc90000007078 EFLAGS: 00000046
RAX: ffff88810f2bbb80 RBX: 0000000000000000 RCX: 0000000080000303
RDX: 0000000000000000 RSI: ffffffff8e24879f RDI: ffffffff8c4bdb80
RBP: ffffffff8177827f R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90000007218 R11: ffffffff81b1fa10 R12: 0000000000000002
R13: ffffffff8eb59c60 R14: 0000000000000000 R15: 0000000000000246
FS:  0000000000000000(0000) GS:ffff88818d954000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0ec147c440 CR3: 000000018b110000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 lock_acquire+0xcd/0x350
 unwind_next_frame+0xac/0x2550
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_noprof+0x2a0/0x5f0
 skb_clone+0x212/0x3a0
 vxcan_xmit+0x1e0/0x780
 dev_hard_start_xmit+0x2cd/0x830
 __dev_queue_xmit+0x14c0/0x3820
 can_send+0x941/0xd30
 can_can_gw_rcv+0xd09/0xfd0
 can_rcv_filter+0x126/0x7a0
 can_receive+0x2c6/0x440
 can_rcv+0x1f9/0x330
 process_backlog+0xbf0/0x1860
 __napi_poll+0xaa/0x330
 net_rx_action+0x61d/0xf50
 handle_softirqs+0x225/0x840
 do_softirq+0x76/0xd0
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0xf8/0x130
 neigh_periodic_work+0xc23/0xe40
 process_scheduled_works+0xa8e/0x14e0
 worker_thread+0xa47/0xfb0
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
