INFO: task syz.2.856:12019 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.856       state:D stack:25128 pid:12019 tgid:12018 ppid:10626  task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 super_lock+0x1c8/0x3b0
 __iterate_supers+0x126/0x290
 __se_sys_quotactl+0x353/0x950
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efde558eba9
RSP: 002b:00007efde64f0038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007efde57d5fa0 RCX: 00007efde558eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 00007efde5611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efde57d6038 R14: 00007efde57d5fa0 R15: 00007ffd010dcb28
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5677:
 #0: ffff8881066c30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
1 lock held by syz.8.618/10417:
 #0: ffff888047af60e0 (&type->s_umount_key#80/1){+.+.}-{4:4}, at: alloc_super+0x204/0x970
1 lock held by syz.1.1288/14850:
 #0: ffffffff8dfe16a8 (wq_pool_mutex){+.+.}-{4:4}, at: __alloc_workqueue+0x9eb/0x1b70
1 lock held by syz.5.1290/14854:
 #0: ffffffff8dfe16a8 (wq_pool_mutex){+.+.}-{4:4}, at: __alloc_workqueue+0x9eb/0x1b70

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

NMI backtrace for cpu 1
CPU: 1 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5818 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:lockdep_hardirqs_on_prepare+0x4a/0x2a0
Code: 06 0e 00 0f 84 9d 01 00 00 65 8b 05 f0 69 03 11 a9 00 00 f0 00 0f 85 8b 01 00 00 65 8b 05 de a9 03 11 85 c0 0f 85 7c 01 00 00 <65> 8b 05 97 a6 03 11 85 c0 0f 85 6d 01 00 00 83 3d b0 bc 0e 18 00
RSP: 0018:ffffc90002ff7860 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000201 RCX: 700a124d30525c00
RDX: 0000000000000000 RSI: ffffffff8be33960 RDI: ffffffff8be33920
RBP: ffffc90002ff7930 R08: ffffffff8fa3a037 R09: 1ffffffff1f47406
R10: dffffc0000000000 R11: fffffbfff1f47407 R12: ffffffff89f12b9a
R13: ffff888027d70d00 R14: dffffc0000000000 R15: 1ffff920005fef14
FS:  000055558b4c9500(0000) GS:ffff8880b8615000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000006400 CR3: 000000010f802000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 trace_hardirqs_on+0x28/0x40
 __local_bh_enable_ip+0x12d/0x1c0
 tcp_recvmsg+0x1fa/0x810
 inet_recvmsg+0x147/0x250
 sock_recvmsg+0x1a8/0x270
 sock_read_iter+0x231/0x2f0
 vfs_read+0x55a/0xa30
 ksys_read+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fceadf8d57d
Code: a8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb b5 e8 a8 48 00 00 0f 1f 84 00 00 00 00 00 80 3d e1 af 21 00 00 74 17 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 5b c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec
RSP: 002b:00007ffe84ab0558 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fceadf8d57d
RDX: 0000000000000004 RSI: 00007ffe84ab056c RDI: 0000000000000003
RBP: 0000000000000000 R08: 000000002601e29b R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe84ab0980
R13: 0000000000000004 R14: 00007ffe84ab056c R15: 00007ffe84ab0600
 </TASK>
