INFO: task syz-executor:12010 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:22312 pid:12010 tgid:12010 ppid:1      task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1821/0x5740
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7f7/0x1550
 del_device_store+0xd7/0x370
 kernfs_fop_write_iter+0x3af/0x540
 vfs_write+0x61d/0xb90
 ksys_write+0x150/0x270
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f97e355d68e
RSP: 002b:00007ffc1ac11918 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000555577b37500 RCX: 00007f97e355d68e
RDX: 0000000000000001 RSI: 00007ffc1ac119a0 RDI: 0000000000000005
RBP: 00007f97e36335f2 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffc1ac119a0 R14: 00007f97e4344620 R15: 0000000000000003
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e95cda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
1 lock held by dhcpcd/5355:
 #0: ffffffff8fdd1280 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_deladdr+0x1c1/0x790
2 locks held by getty/5438:
 #0: ffff8881147610a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034732e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
2 locks held by kworker/1:13/8065:
3 locks held by kworker/u9:20/4520:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90007237c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffffffff8fdd1280 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60
3 locks held by kworker/0:7/6327:
 #0: ffff88810006b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90006677c40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffffffff8fdd1280 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20
5 locks held by kworker/u8:0/11902:
 #0: ffff8881012b5940 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90007797c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffffffff8fdc2568 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800
 #3: ffffffff8fdd1280 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x940
 #4: ffffffff8e962f78 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580
7 locks held by syz-executor/12001:
 #0: ffff888169e98410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff8881ad890880 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88810b4c03c8 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f650640 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
 #4: ffff8881aa33f128 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x870
 #5: ffff88819ab63258 (&devlink->lock_key#15){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x170
 #6: ffffffff8fdd1280 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0
4 locks held by syz-executor/12010:
 #0: ffff888169e98410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff88817297f880 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88810b4c03c8 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f650640 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
4 locks held by syz-executor/12093:
 #0: ffff888169e98410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff888106381880 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88810b4c03c8 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f650640 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
4 locks held by syz-executor/12101:
 #0: ffff888169e98410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff888195e27480 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88810b4c03c8 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f650640 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
4 locks held by syz-executor/12109:
 #0: ffff888169e98410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff888194b49480 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88810b4c03c8 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f650640 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
4 locks held by syz-executor/12204:
 #0: ffff888169e98410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff8881134bac80 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88810b4c03c8 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f650640 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
3 locks held by kworker/u11:2/12207:
 #0: ffff8881176ed140 ((wq_completion)hci5){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90007417c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffff88801bc60ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400
4 locks held by syz-executor/12212:
 #0: ffff888169e98410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff88811ed6ec80 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88810b4c03c8 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f650640 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
4 locks held by syz-executor/12218:
 #0: ffff888169e98410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff888022ef0880 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88810b4c03c8 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f650640 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
1 lock held by syz-executor/12316:
 #0: ffffffff8fdd1280 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0
1 lock held by syz-executor/12326:
 #0: ffffffff8fdd1280 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0

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

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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd3/0x1030
 kthread+0x389/0x470
 ret_from_fork+0x514/0xb70
 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: 8065 Comm: kworker/1:13 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_long br_multicast_gc_work
RIP: 0010:__sysvec_apic_timer_interrupt+0x6/0x430
Code: 00 0f 30 31 c0 e9 8a fe 38 0a cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 41 57 <41> 56 41 54 53 48 89 fb 49 bc 00 00 00 00 00 fc ff df 48 c7 c7 20
RSP: 0018:ffffc90000a08680 EFLAGS: 00000016
RAX: 1ffff110478c487c RBX: ffffc90000a086a8 RCX: 0000000000010100
RDX: 0000000000010100 RSI: ffffffff8c28afc0 RDI: ffffc90000a086a8
RBP: 0000000000000000 R08: ffffffff90311cf7 R09: 1ffffffff206239e
R10: dffffc0000000000 R11: fffffbfff206239f R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8882a927a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faba97f6d58 CR3: 000000000e74a000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 sysvec_apic_timer_interrupt+0x52/0xc0
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:unwind_next_frame+0x1d5/0x2550
Code: 48 83 f3 01 48 c7 c2 20 a5 c9 8b 49 29 dc 0f 84 b2 02 00 00 49 81 fc 00 00 00 81 0f 92 c0 49 81 fc f8 2c ae 8b 0f 93 c1 08 c1 <0f> 85 05 01 00 00 48 c7 c0 00 00 00 81 4d 89 e7 49 29 c7 49 c1 ef
RSP: 0018:ffffc90000a08758 EFLAGS: 00000246
RAX: 1ffff92000141100 RBX: 0000000000000001 RCX: 0000000000000100
RDX: ffffffff8bc9a520 RSI: ffffffff8c28afc0 RDI: ffffffff8c28af80
RBP: dffffc0000000000 R08: ffffffff8176f256 R09: ffffffff8e95cda0
R10: ffffc90000a08878 R11: ffffffff81b0efc0 R12: ffffffff8981f36e
R13: 1ffff92000141105 R14: ffffc90000a08828 R15: ffffc90000a08870
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5c/0x80
 kfree+0x1c5/0x640
 ref_tracker_free+0x522/0x840
 dst_destroy+0x10f/0x350
 rcu_core+0x7cd/0x1070
 handle_softirqs+0x22a/0x840
 __irq_exit_rcu+0xca/0x220
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:br_multicast_gc_work+0x4/0x240
Code: ff e8 b0 af b1 f7 e9 a1 fe ff ff 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 f3 0f 1e fa <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec 80 00
RSP: 0018:ffffc90007ef7ad8 EFLAGS: 00000246
RAX: 1ffff1102cbf3ac3 RBX: ffffffff818e9820 RCX: ffff8881bf113b00
RDX: 0000000000000000 RSI: ffffffff8c28afc0 RDI: ffff88819a78d908
RBP: ffffc90007ef7ce8 R08: ffffffff90311cf7 R09: 1ffffffff206239e
R10: dffffc0000000000 R11: ffffffff8a7f5370 R12: ffff8881bf113fc4
R13: ffff88819a78d908 R14: dffffc0000000000 R15: ffff888165f9d618
 process_scheduled_works+0xb5d/0x1860
 worker_thread+0xa53/0xfc0
 kthread+0x389/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
