INFO: task syz.1.1121:10163 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1121      state:D stack:24816 pid:10163 tgid:10162 ppid:5845   task_flags:0x480140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 blk_mq_freeze_queue_wait+0xf4/0x170
 queue_limits_commit_update_frozen+0x5d/0x3e0
 nbd_set_size+0x47e/0x6a0
 nbd_genl_size_set+0x2eb/0x3c0
 nbd_genl_reconfigure+0x409/0x1870
 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: 0033:0x7f2352f8ebe9
RSP: 002b:00007f2353eb2038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f23531c5fa0 RCX: 00007f2352f8ebe9
RDX: 0000000000000000 RSI: 0000200000006780 RDI: 0000000000000006
RBP: 00007f2353011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f23531c6038 R14: 00007f23531c5fa0 R15: 00007ffee5276b68
 </TASK>
INFO: task syz.2.1122:10169 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1122      state:D stack:27800 pid:10169 tgid:10167 ppid:5851   task_flags:0x400040 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: 0033:0x7f3dd4b90a7c
RSP: 002b:00007f3dd2df4ec0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f3dd2df4fc0 RCX: 00007f3dd4b90a7c
RDX: 0000000000000020 RSI: 00007f3dd2df5010 RDI: 0000000000000004
RBP: 0000000000000000 R08: 00007f3dd2df4f14 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000004
R13: 00007f3dd2df4f68 R14: 00007f3dd2df5010 R15: 0000000000000000
 </TASK>
INFO: task syz.0.1125:10177 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1125      state:D stack:27944 pid:10177 tgid:10176 ppid:5849   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_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: 0033:0x7f96aad8ebe9
RSP: 002b:00007f96abb6f038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f96aafc5fa0 RCX: 00007f96aad8ebe9
RDX: 0000000000000000 RSI: 00002000000001c0 RDI: 0000000000000004
RBP: 00007f96aae11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f96aafc6038 R14: 00007f96aafc5fa0 R15: 00007fff5fb34a18
 </TASK>
INFO: task syz.0.1125:10178 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1125      state:D stack:27944 pid:10178 tgid:10176 ppid:5849   task_flags:0x400040 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_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: 0033:0x7f96aad8ebe9
RSP: 002b:00007f96abb4e038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f96aafc6090 RCX: 00007f96aad8ebe9
RDX: 0000000000000000 RSI: 00002000000001c0 RDI: 0000000000000004
RBP: 00007f96aae11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f96aafc6128 R14: 00007f96aafc6090 R15: 00007fff5fb34a18
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
1 lock held by klogd/5284:
 #0: ffff888136639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140
2 locks held by getty/5673:
 #0: ffff8880271f70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900028fe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
1 lock held by udevd/9264:
 #0: ffff888021bf3358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
6 locks held by syz.1.1121/10163:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790
 #2: ffff888021b1d230 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_genl_reconfigure+0x36f/0x1870
 #3: ffff888108116928 (&q->limits_lock){+.+.}-{4:4}, at: nbd_set_size+0x292/0x6a0
 #4: ffff8881081162c8 (&q->q_usage_counter(io)#50){++++}-{0:0}, at: queue_limits_commit_update_frozen+0x5d/0x3e0
 #5: ffff888108116300 (&q->q_usage_counter(queue)#34){+.+.}-{0:0}, at: queue_limits_commit_update_frozen+0x5d/0x3e0
2 locks held by syz.2.1122/10169:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790
2 locks held by syz.0.1125/10177:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790
2 locks held by syz.0.1125/10178:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790
2 locks held by syz-executor/10183:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790
2 locks held by syz-executor/10185:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790
2 locks held by syz-executor/10200:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790
2 locks held by syz-executor/10255:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790
2 locks held by syz-executor/10257:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790
2 locks held by syz-executor/10272:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790
2 locks held by syz-executor/10283:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790
2 locks held by syz-executor/10285:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790
2 locks held by syz-executor/10300:
 #0: ffffffff8f59e0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40
 #1: ffffffff8f59dec8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790

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

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: 5897 Comm: kworker/u8:4 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: bat_events batadv_nc_worker
RIP: 0010:check_preemption_disabled+0x63/0x120
Code: 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d e9 81 c9 02 00 cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 <74> c8 65 4c 8b 3c 25 08 80 a0 92 41 f6 47 2f 04 74 0a 41 83 bf 18
RSP: 0018:ffffc900035179e0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000206 RCX: 0000000080000000
RDX: 0000000000000000 RSI: ffffffff8d9cbb73 RDI: ffffffff8be33800
RBP: ffffc90003517c70 R08: ffffffff8fa38e37 R09: 1ffffffff1f471c6
R10: dffffc0000000000 R11: fffffbfff1f471c7 R12: ffff888107c70800
R13: ffffffff818b5c6f R14: ffffc90003517bc0 R15: ffff888108779cc0
FS:  0000000000000000(0000) GS:ffff8881a3c18000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055946092ae68 CR3: 000000000df36000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_release+0xbc/0x3e0
 process_scheduled_works+0xbbd/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
