INFO: task syz.1.5284:18423 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.5284      state:D stack:23384 pid:18423 tgid:18415 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
 disable_device+0x1c6/0x320
 __ib_unregister_device+0x2cb/0x3f0
 ib_unregister_device_and_put+0xb8/0xf0
 nldev_dellink+0x2d1/0x320
 rdma_nl_rcv+0x6ae/0x980
 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: 0033:0x7f657b18ec29
RSP: 002b:00007f657bf44038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f657b3d6090 RCX: 00007f657b18ec29
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000000000004
RBP: 00007f657b211e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f657b3d6128 R14: 00007f657b3d6090 R15: 00007ffccefb4518
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/0:0/9:
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900000c7bc0 (xfrm_state_gc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
1 lock held by khungtaskd/34:
 #0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5670:
 #0: ffff88801f6f00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029032f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
1 lock held by sshd/5825:
2 locks held by syz-executor/5847:
4 locks held by kworker/u8:2/5855:
 #0: ffff88801b2f7148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc9000430fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f52df10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800
 #3: ffff888108890700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300
2 locks held by syz.1.5284/18423:
 #0: ffffffff99e48958 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv+0x302/0x980
 #1: ffff888108890700 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x284/0x3f0
3 locks held by syz-executor/18996:
2 locks held by syz.2.8518/26033:
 #0: ffff88801c39dcd8 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x3b/0x100
 #1: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730
1 lock held by syz.2.8518/26034:
 #0: ffff888103609a08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240

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

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+0x439/0x7d0
 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: 5847 Comm: syz-executor 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:debug_check_no_obj_freed+0x212/0x470
Code: c0 0f 84 45 02 00 00 4d 89 fe 49 c1 ee 03 48 b8 00 00 00 00 00 fc ff df 41 80 3c 06 00 74 08 4c 89 ff e8 31 5d 52 fd 49 8b 07 <48> 89 44 24 18 4d 8d 67 18 4c 89 e0 48 c1 e8 03 48 b9 00 00 00 00
RSP: 0018:ffffc900042bfa38 EFLAGS: 00000046
RAX: ffff88801c36c690 RBX: 0000000000000000 RCX: 1ffffffff339aa17
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc900042bf920
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000857f24 R12: ffff888114e53000
R13: ffff888114e54000 R14: 1ffff1100386d8cb R15: ffff88801c36c658
FS:  0000555564da4500(0000) GS:ffff8881a3c39000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f43aa707d60 CR3: 000000010c550000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __free_frozen_pages+0x4dd/0xd30
 vfree+0x25a/0x400
 kcov_close+0x28/0x50
 __fput+0x44c/0xa70
 task_work_run+0x1d4/0x260
 do_exit+0x6b5/0x2300
 do_group_exit+0x21c/0x2d0
 __x64_sys_exit_group+0x3f/0x40
 x64_sys_call+0x21f7/0x2200
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f43a998ec29
Code: Unable to access opcode bytes at 0x7f43a998ebff.
RSP: 002b:00007ffc8c1a6b48 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f43a9a1367b RCX: 00007f43a998ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000043
RBP: 00007f43a9a1368d R08: 00007ffc8c1a48e7 R09: 00000000000927c0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 00000000000927c0 R14: 000000000006d61d R15: 00007ffc8c1a6cf0
 </TASK>
