INFO: task syz.0.4609:25841 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.4609      state:D stack:28800 pid:25841 tgid:25840 ppid:8160   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x5300
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 sync_bdevs+0x27e/0x470
 __ia32_sys_sync+0xc5/0x120
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa86639c799
RSP: 002b:00007fa867256028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fa866615fa0 RCX: 00007fa86639c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fa866615fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa866616038 R14: 00007fa866615fa0 R15: 00007ffe3e096488
 </TASK>
INFO: task syz.0.4609:25842 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.4609      state:D stack:28800 pid:25842 tgid:25840 ppid:8160   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x5300
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 sync_bdevs+0x27e/0x470
 __ia32_sys_sync+0xc5/0x120
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa86639c799
RSP: 002b:00007fa867235028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fa866616090 RCX: 00007fa86639c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fa866616090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa866616128 R14: 00007fa866616090 R15: 00007ffe3e096488
 </TASK>
INFO: task syz.0.4609:25845 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.4609      state:D stack:27720 pid:25845 tgid:25840 ppid:8160   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x5300
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 sync_bdevs+0x27e/0x470
 __ia32_sys_sync+0xc5/0x120
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa86639c799
RSP: 002b:00007fa867214028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fa866616180 RCX: 00007fa86639c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fa866616180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa866616218 R14: 00007fa866616180 R15: 00007ffe3e096488
 </TASK>
INFO: task syz.0.4609:25846 blocked for more than 144 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.4609      state:D stack:27720 pid:25846 tgid:25840 ppid:8160   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x5300
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 sync_bdevs+0x27e/0x470
 __ia32_sys_sync+0xc5/0x120
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa86639c799
RSP: 002b:00007fa8671f3028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fa866616270 RCX: 00007fa86639c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fa866616270 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa866616308 R14: 00007fa866616270 R15: 00007ffe3e096488
 </TASK>
INFO: task syz.0.4609:25849 blocked for more than 144 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.4609      state:D stack:27720 pid:25849 tgid:25840 ppid:8160   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x5300
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 sync_bdevs+0x27e/0x470
 __ia32_sys_sync+0xc5/0x120
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa86639c799
RSP: 002b:00007fa8671d2028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fa866616360 RCX: 00007fa86639c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fa866616360 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa8666163f8 R14: 00007fa866616360 R15: 00007ffe3e096488
 </TASK>
INFO: task syz.0.4609:25850 blocked for more than 144 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.4609      state:D stack:27720 pid:25850 tgid:25840 ppid:8160   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x5300
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 sync_bdevs+0x27e/0x470
 __ia32_sys_sync+0xc5/0x120
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa86639c799
RSP: 002b:00007fa8671b1028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fa866616450 RCX: 00007fa86639c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fa866616450 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa8666164e8 R14: 00007fa866616450 R15: 00007ffe3e096488
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_exp_gp_kthr/18:
1 lock held by khungtaskd/34:
 #0: ffffffff8e75e560 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
1 lock held by dhcpcd/5552:
 #0: ffffffff8fbd1a08 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x32b/0x1b30
2 locks held by getty/5634:
 #0: ffff88810eb160a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900032402f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
3 locks held by kworker/u10:8/7658:
 #0: ffff8881000ac148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0
 #1: ffffc900035b7c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0
 #2: ffffffff8fbd1a08 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60
1 lock held by udevd/22397:
 #0: ffff888104721358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.0.4609/25841:
 #0: ffff888104721358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470
1 lock held by syz.0.4609/25842:
 #0: ffff888104721358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470
1 lock held by syz.0.4609/25845:
 #0: ffff888104721358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470
1 lock held by syz.0.4609/25846:
 #0: ffff888104721358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470
1 lock held by syz.0.4609/25849:
 #0: ffff888104721358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470
1 lock held by syz.0.4609/25850:
 #0: ffff888104721358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470
5 locks held by kworker/u8:5/26544:
 #0: ffff8881012ae148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0
 #1: ffffc90003ea7c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0
 #2: ffffffff8fbc3270 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800
 #3: ffff888113ded528 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_destruct+0x116/0x310
 #4: ffffffff8e7646c0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580
8 locks held by syz-executor/29314:
 #0: ffff88810d7f4420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff8881aa08e888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88816d7a5878 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f445d08 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
 #4: ffff88817246b0e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x860
 #5: ffff88817246c250 (&devlink->lock_key#23){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x170
 #6: ffffffff8fbd1a08 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x10b/0x730
 #7: ffffffff8e7647f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770
2 locks held by syz.9.5332/29357:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
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+0xfd9/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 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: 26544 Comm: kworker/u8:5 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:mark_lock+0x2f/0x190
Code: 41 55 41 54 53 8b 46 20 89 c1 81 e1 00 00 03 00 83 f9 01 bb 09 00 00 00 83 db 00 83 fa 08 0f 45 da bd 01 00 00 00 89 d9 d3 e5 <25> ff 1f 00 00 48 0f a3 05 c4 d4 81 12 73 10 48 69 c0 c8 00 00 00
RSP: 0018:ffffc90003ea75c8 EFLAGS: 00000002
RAX: 0000000000040a48 RBX: 0000000000000002 RCX: 0000000000000002
RDX: 0000000000000002 RSI: ffff888176b4a8c0 RDI: ffff888176b49d40
RBP: 0000000000000004 R08: ffffffff9011e3b7 R09: 1ffffffff2023c76
R10: dffffc0000000000 R11: fffffbfff2023c77 R12: ffff888176b4a8c0
R13: ffffffff8b770fe0 R14: ffff888176b4a898 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8882a9463000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f36cb1e92f8 CR3: 00000001776cc000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lockdep_hardirqs_on_prepare+0x110/0x260
 trace_hardirqs_on+0x28/0x40
 __local_bh_enable_ip+0xd0/0x130
 batadv_dat_free+0x298/0x380
 batadv_mesh_free+0x74/0x140
 batadv_meshif_free+0x15/0x20
 netdev_run_todo+0xc1f/0xde0
 default_device_exit_batch+0x986/0xa00
 ops_undo_list+0x52b/0x940
 cleanup_net+0x56b/0x800
 process_scheduled_works+0xb6e/0x18c0
 worker_thread+0xa53/0xfc0
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>
