INFO: task syz.1.450:10025 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.450       state:D stack:24960 pid:10025 tgid:10024 ppid:9912   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x61e/0x920
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 user_get_super+0xc8/0x120
 __se_sys_quotactl+0x540/0x9e0
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1fe619c799
RSP: 002b:00007f1fe702d028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f1fe6415fa0 RCX: 00007f1fe619c799
RDX: 0000000000000000 RSI: 0000200000000040 RDI: ffffffff80000801
RBP: 00007f1fe6232c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000100 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1fe6416038 R14: 00007f1fe6415fa0 R15: 00007fff10dad958
 </TASK>
INFO: task syz.1.450:10033 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.450       state:D stack:28832 pid:10033 tgid:10024 ppid:9912   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x61e/0x920
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 user_get_super+0xc8/0x120
 __se_sys_quotactl+0x540/0x9e0
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1fe619c799
RSP: 002b:00007f1fe700c028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f1fe6416090 RCX: 00007f1fe619c799
RDX: 0000000000000000 RSI: 0000200000000340 RDI: ffffffff80000801
RBP: 00007f1fe6232c99 R08: 0000000000000000 R09: 0000000000000000
R10: 00002000000002c0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1fe6416128 R14: 00007f1fe6416090 R15: 00007fff10dad958
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e75e420 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by dhcpcd/5553:
2 locks held by getty/5636:
 #0: ffff88816a3da0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
2 locks held by syz-executor/5826:
2 locks held by syz-executor/7265:
5 locks held by kworker/u8:5/9435:
 #0: ffff8881012ae148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830
 #1: ffffc9000955fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830
 #2: ffffffff8fbbe5f0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800
 #3: ffffffff8fbccd88 (rtnl_mutex){+.+.}-{4:4}, at: ieee80211_unregister_hw+0x55/0x2c0
 #4: ffff888112bb0788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_netdev_notifier_call+0x1a8/0x1470
2 locks held by syz-executor/9693:
1 lock held by syz.1.450/10025:
 #0: ffff8881177de0e0 (&type->s_umount_key#78){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.1.450/10033:
 #0: ffff8881177de0e0 (&type->s_umount_key#78){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
2 locks held by syz-executor/12805:
 #0: ffffffff8f308c88 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250
 #1: ffffffff8fbccd88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0
2 locks held by syz.1.747/12837:
3 locks held by syz.4.746/12839:
2 locks held by dhcpcd/12849:
 #0: ffff8881a98f6260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe10
 #1: ffffffff8e7646b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770

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

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+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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7265 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:__lock_acquire+0xa54/0x2cf0
Code: c7 c6 bd 13 01 8e 67 48 0f b9 3a 90 31 c0 48 83 78 40 00 0f 84 5f 1d 00 00 41 8b 45 20 25 ff 1f 00 00 48 0f a3 05 6c 0f 82 12 <73> 10 48 69 c0 c8 00 00 00 48 8d 80 10 a4 c4 93 eb 32 83 3d 33 9f
RSP: 0018:ffffc90004c2f258 EFLAGS: 00000003
RAX: 0000000000000007 RBX: 000000002bc53b3f RCX: 0000000002e8b263
RDX: 000000006e0285a2 RSI: 0000000080d5f57a RDI: ffff88811112d7c0
RBP: bf0cd54c00000000 R08: ffffffff81767de5 R09: ffffffff8e75e420
R10: ffffc90004c2f538 R11: ffffffff81b0bfa0 R12: ffff88811112e340
R13: ffff88811112e340 R14: ffff88811112d7c0 R15: 0000000000000001
FS:  000055557c06d500(0000) GS:ffff88818de63000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b32c05e131 CR3: 000000011cb62000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_acquire+0xf0/0x2e0
 unwind_next_frame+0xc2/0x23c0
 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
 kmem_cache_free+0x187/0x630
 xfs_trans_alloc+0x49c/0x9b0
 xfs_vn_sync_lazytime+0xaf/0x150
 sync_lazytime+0x12d/0x2d0
 iput+0x230/0xe80
 __dentry_kill+0x1a2/0x5e0
 shrink_kill+0xa9/0x2c0
 shrink_dentry_list+0x2e0/0x5e0
 shrink_dcache_tree+0xcf/0x310
 shrink_dcache_for_umount+0xa8/0x1f0
 generic_shutdown_super+0x6f/0x2d0
 kill_block_super+0x44/0x90
 xfs_kill_sb+0x15/0x50
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x437/0x4d0
 task_work_run+0x1d9/0x270
 exit_to_user_mode_loop+0xed/0x480
 do_syscall_64+0x32d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa35779d9d7
Code: a2 c7 05 1c fd 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007fffb462b698 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fa357832050 RCX: 00007fa35779d9d7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffb462b750
RBP: 00007fffb462b750 R08: 00007fffb462c750 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fffb462c7e0
R13: 00007fa357832050 R14: 0000000000036020 R15: 00007fffb462c820
 </TASK>
