INFO: task syz.1.1352:10950 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1352      state:D stack:23080 pid:10950 tgid:10949 ppid:5841   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: 0033:0x7ffa3b78ebe9
RSP: 002b:00007ffa3c672038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ffa3b9b5fa0 RCX: 00007ffa3b78ebe9
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000000000003
RBP: 00007ffa3b811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffa3b9b6038 R14: 00007ffa3b9b5fa0 R15: 00007ffd10c95ce8
 </TASK>
INFO: task syz.2.1373:11022 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1373      state:D stack:21720 pid:11022 tgid:11021 ppid:5851   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 rdma_dev_change_netns+0x39/0x300
 rdma_dev_exit_net+0x203/0x340
 ops_undo_list+0x49a/0x990
 setup_net+0x2d3/0x320
 copy_net_ns+0x31b/0x4d0
 create_new_namespaces+0x3f3/0x720
 unshare_nsproxy_namespaces+0x11c/0x170
 ksys_unshare+0x4c8/0x8c0
 __x64_sys_unshare+0x38/0x50
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9e4f58ebe9
RSP: 002b:00007f9e50349038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f9e4f7b5fa0 RCX: 00007f9e4f58ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000062040200
RBP: 00007f9e4f611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9e4f7b6038 R14: 00007f9e4f7b5fa0 R15: 00007ffe561f7c58
 </TASK>
INFO: lockdep is turned off.
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: 17874 Comm: syz.6.3260 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:check_preemption_disabled+0x25/0x120
Code: 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 be 7e 26 07 48 89 44 24 08 65 8b 05 c6 7e 26 07 65 8b 0d bb 7e 26 07 <f7> c1 ff ff ff 7f 74 23 65 48 8b 0d 9b 7e 26 07 48 3b 4c 24 08 0f
RSP: 0000:ffffc90006e3ec38 EFLAGS: 00000282
RAX: 0000000000000001 RBX: ffffffff8206b4e7 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8be33660 RDI: ffffffff8be33620
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff82350a40 R12: 0000000000000001
R13: ffffffff8206b4e7 R14: ffffffff8e139ee0 R15: ffff88810f76b010
FS:  00007f6bad66b6c0(0000) GS:ffff8881a3c1a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f10d1561000 CR3: 0000000131efa000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 rcu_is_watching+0x15/0xb0
 lock_release+0x4b/0x3e0
 list_lru_count_one+0x24b/0x2c0
 super_cache_count+0x1a7/0x240
 do_shrink_slab+0x91/0x1110
 shrink_slab+0xd74/0x10d0
 shrink_one+0x28a/0x7c0
 shrink_node+0x314e/0x3760
 do_try_to_free_pages+0x668/0x1960
 try_to_free_pages+0x8a2/0xdd0
 __alloc_pages_direct_reclaim+0x144/0x300
 __alloc_pages_slowpath+0x5ff/0xce0
 __alloc_frozen_pages_noprof+0x319/0x370
 alloc_pages_bulk_noprof+0x560/0x710
 kasan_populate_vmalloc+0xba/0x1a0
 alloc_vmap_area+0xd51/0x1490
 __get_vm_area_node+0x1f8/0x300
 get_vm_area+0x80/0xb0
 arena_map_alloc+0x256/0x520
 map_create+0xaa3/0x14d0
 __sys_bpf+0x60f/0x870
 __x64_sys_bpf+0x7c/0x90
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6bac78ebe9
Code: Unable to access opcode bytes at 0x7f6bac78ebbf.
RSP: 002b:00007f6bad66b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f6bac9b6090 RCX: 00007f6bac78ebe9
RDX: 0000000000000050 RSI: 0000200000003940 RDI: 0000000000000000
RBP: 00007f6bac811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6bac9b6128 R14: 00007f6bac9b6090 R15: 00007ffc313f0f68
 </TASK>
