INFO: task syz.5.1237:12061 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1237      state:D stack:27720 pid:12061 tgid:12060 ppid:10953  task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 super_lock+0x2a9/0x3b0
 __iterate_supers+0x126/0x290
 __se_sys_quotactl+0x353/0x950
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7effe758ebe9
RSP: 002b:00007effe8371038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007effe77b5fa0 RCX: 00007effe758ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 00007effe7611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007effe77b6038 R14: 00007effe77b5fa0 R15: 00007fffc7671f98
 </TASK>
INFO: lockdep is turned off.
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: 12080 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_release+0x44/0x3e0
Code: 8b 05 70 e4 02 11 48 89 44 24 28 0f 1f 44 00 00 65 8b 05 73 e4 02 11 83 f8 08 0f 83 9a 02 00 00 89 c0 48 0f a3 05 5c 17 06 0e <73> 16 e8 45 f1 08 00 84 c0 75 0d f6 05 7e fd ef 0d 01 0f 84 ad 02
RSP: 0018:ffffc900045bf4d0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 00007fff1b1ee201 RCX: dffffc0000000000
RDX: ffffffff902a8100 RSI: ffffffff8172c195 RDI: ffffffff8e139ea0
RBP: dffffc0000000000 R08: 0000000000000022 R09: 0000000000000000
R10: ffffc900045bf658 R11: ffffffff81ac3810 R12: 00007fff1b1ee2b8
R13: ffffffff8172c195 R14: ffffffff8e139ea0 R15: ffffffff8172c195
FS:  0000555578848500(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6d82e44000 CR3: 000000010d7bc000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 unwind_next_frame+0x19a9/0x2390
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 save_stack+0xf5/0x1f0
 __reset_page_owner+0x71/0x1f0
 __free_frozen_pages+0xbc4/0xd30
 vfree+0x25a/0x400
 kcov_close+0x28/0x50
 __fput+0x44c/0xa70
 task_work_run+0x1d4/0x260
 do_exit+0x6b5/0x2300
 do_group_exit+0x21c/0x2d0
 get_signal+0x1286/0x1340
 arch_do_signal_or_restart+0x9a/0x750
 exit_to_user_mode_loop+0x75/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe50ad84e13
Code: Unable to access opcode bytes at 0x7fe50ad84de9.
RSP: 002b:00007fff1b1ee2b8 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000000000002f33 RCX: 00007fe50ad84e13
RDX: 0000000040000000 RSI: 00007fff1b1ee2cc RDI: 00000000ffffffff
RBP: 00007fff1b1ee2cc R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
 </TASK>
