INFO: task syz-executor:22376 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:22392 pid:22376 tgid:22376 ppid:1      task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x14bc/0x5000
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 new_device_store+0x12c/0x6f0
 kernfs_fop_write_iter+0x3af/0x540
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2db7b8e27f
RSP: 002b:00007ffc2df53520 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f2db7b8e27f
RDX: 0000000000000003 RSI: 00007ffc2df53570 RDI: 0000000000000005
RBP: 00007f2db7bf280c R08: 0000000000000000 R09: 00007ffc2df53377
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 00007ffc2df53570 R14: 00007f2db8914620 R15: 0000000000000003
 </TASK>

Showing all locks held in the system:
6 locks held by ksoftirqd/0/15:
1 lock held by khungtaskd/35:
 #0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
4 locks held by kworker/u10:12/3614:
 #0: ffff888100089948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770
 #1: ffffc9000b29fb80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770
 #2: ffffffff8f311c88 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60
 #3: ffffffff8df47578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730
2 locks held by getty/5655:
 #0: ffff888113ad50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460
6 locks held by kworker/u8:5/5870:
 #0: ffff888100ef7948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770
 #1: ffffc90005167b80 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770
 #2: ffffffff8f304bf0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7a0
 #3: ffff88816861e0e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x10a/0x3d0
 #4: ffff88816861f250 (&devlink->lock_key#2){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x11c/0x3d0
 #5: ffffffff8f311c88 (rtnl_mutex){+.+.}-{4:4}, at: unregister_nexthop_notifier+0x17/0x40
3 locks held by kworker/u8:4/22354:
 #0: ffff88816fa6a948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770
 #1: ffffc90004e07b80 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770
 #2: ffffffff8f311c88 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0
4 locks held by syz-executor/22376:
 #0: ffff888111eec420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xb30
 #1: ffff88816ae98088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88816e416a58 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8eb9f9e8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x12c/0x6f0
7 locks held by syz-executor/22385:
 #0: ffff888111eec420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xb30
 #1: ffff8881bd5d8c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88816e416b48 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8eb9f9e8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360
 #4: ffff8881b03730e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800
 #5: ffff8881b0375250 (&devlink->lock_key#4){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160
 #6: ffffffff8f311c88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0
2 locks held by syz-executor/22422:
 #0: ffffffff8f304bf0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x3cc/0x570
 #1: ffffffff8f311c88 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x990
2 locks held by syz-executor/22430:
 #0: ffffffff8ea6f268 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250
 #1: ffffffff8f311c88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90
2 locks held by syz-executor/22435:
 #0: ffffffff8eb69748 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250
 #1: ffffffff8f311c88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90
2 locks held by syz-executor/22438:
 #0: ffffffff8f841fd8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250
 #1: ffffffff8f311c88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90
2 locks held by kworker/u10:0/22466:
 #0: ffff888100089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770
 #1: ffffc90003577b80 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770

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

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+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xf95/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x599/0xb30
 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: 15 Comm: ksoftirqd/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:__kasan_check_read+0x6/0x20
Code: 00 99 ff fe 31 ed eb cf cc cc cc cc cc 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 89 f6 <48> 8b 0c 24 31 d2 e9 ef e4 ff ff 66 66 66 66 66 66 2e 0f 1f 84 00
RSP: 0018:ffffc90000146218 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8881026fba80
RDX: 0000000000000100 RSI: 0000000000000008 RDI: ffffffff8f822070
RBP: ffffc900001463c0 R08: ffffffff851ea8a4 R09: ffff888121036910
R10: dffffc0000000000 R11: fffffbfff1f0440f R12: dffffc0000000000
R13: 000000000000002b R14: ffff888121036910 R15: 0000000000000200
FS:  0000000000000000(0000) GS:ffff88818e835000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f48d73f6d00 CR3: 000000000dd3a000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 trace_irq_enable+0x28/0x100
 trace_hardirqs_on+0x18/0x40
 get_random_u16+0x48e/0x930
 cake_get_flow_quantum+0x18e/0x290
 cake_dequeue+0x2b12/0x4cb0
 __qdisc_run+0x23f/0x1510
 qdisc_run+0xc7/0x300
 __dev_queue_xmit+0x186d/0x3140
 ip6_finish_output2+0xf70/0x1480
 ip6_output+0x340/0x550
 synproxy_send_tcp_ipv6+0x543/0x700
 synproxy_send_client_synack_ipv6+0x80e/0xca0
 nft_synproxy_eval_v6+0x36e/0x560
 nft_synproxy_do_eval+0x3d7/0x570
 nft_do_chain+0x40c/0x1920
 nft_do_chain_inet+0x25d/0x340
 nf_hook_slow+0xc5/0x220
 NF_HOOK+0x206/0x3a0
 ip6_input+0x16a/0x270
 NF_HOOK+0x30c/0x3a0
 __netif_receive_skb+0xd3/0x380
 process_backlog+0x622/0x1500
 __napi_poll+0xae/0x320
 net_rx_action+0x672/0xe50
 handle_softirqs+0x27d/0x850
 run_ksoftirqd+0x9b/0x100
 smpboot_thread_fn+0x542/0xa60
 kthread+0x711/0x8a0
 ret_from_fork+0x599/0xb30
 ret_from_fork_asm+0x1a/0x30
 </TASK>
