INFO: task syz.9.3488:15038 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.9.3488      state:D stack:25336 pid:15038 tgid:15037 ppid:11285  task_flags:0x400040 flags:0x00080003
Call Trace:
 <TASK>
 __schedule+0x14ef/0x4fb0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x61e/0x920
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x290
 drop_caches_sysctl_handler+0x97/0x170
 proc_sys_call_handler+0x4cb/0x700
 iter_file_splice_write+0x99b/0x1100
 direct_splice_actor+0x101/0x160
 splice_direct_to_actor+0x53a/0xc70
 do_splice_direct+0x195/0x290
 do_sendfile+0x535/0x7c0
 __se_sys_sendfile64+0xdf/0x1a0
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fabfb79acb9
RSP: 002b:00007fabfc625028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fabfba15fa0 RCX: 00007fabfb79acb9
RDX: 0000200000002080 RSI: 0000000000000003 RDI: 0000000000000004
RBP: 00007fabfb808bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fabfba16038 R14: 00007fabfba15fa0 R15: 00007fff8cd24728
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e341ae0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5659:
 #0: ffff888112f3f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
3 locks held by kworker/1:7/7828:
 #0: ffff888100075948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0
 #1: ffffc90005837bc0 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0
 #2: ffffffff8e347638 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
2 locks held by syz-executor/9330:
2 locks held by syz.9.3488/15038:
 #0: ffff88816caba420 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160
 #1: ffff88811374e0e0 (&type->s_umount_key#72){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.6.4828/18626:
 #0: ffff88811374e0e0 (&type->s_umount_key#72){++++}-{4:4}, at: super_lock+0x2d6/0x3d0

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 35 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+0xf90/0xfe0
 kthread+0x726/0x8b0
 ret_from_fork+0x51b/0xa40
 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: 19085 Comm: syz.4.4989 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
RIP: 0010:kasan_check_range+0x93/0x2c0
Code: 01 00 00 00 00 fc ff df 4d 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 3d 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb <41> 80 3b 00 0f 85 9e 01 00 00 49 ff c3 48 ff c3 75 ee e9 1d 01 00
RSP: 0018:ffffc9000709f570 EFLAGS: 00000286
RAX: ffff88810f64d701 RBX: fffffffffffffff6 RCX: ffffffff8174cae6
RDX: 0000000000000001 RSI: 0000000000000060 RDI: ffffc9000709f628
RBP: 0000000000000000 R08: ffffc9000709f687 R09: 1ffff92000e13ed0
R10: dffffc0000000000 R11: fffff52000e13ec7 R12: 000000000000000c
R13: ffff88810f64d7c0 R14: fffff52000e13ed1 R15: 1ffff92000e13ec5
FS:  00007f92833c26c0(0000) GS:ffff8882a9a09000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff36d15ba0 CR3: 0000000116660000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __asan_memset+0x22/0x50
 __unwind_start+0x36/0x760
 arch_stack_walk+0xe3/0x150
 stack_trace_save+0xa9/0x100
 save_stack+0x122/0x230
 __reset_page_owner+0x71/0x1f0
 __free_frozen_pages+0xb81/0xce0
 vfree+0x25a/0x400
 kcov_close+0x28/0x50
 __fput+0x44f/0xa70
 task_work_run+0x1d9/0x270
 do_exit+0x893/0x25c0
 do_group_exit+0x21b/0x2d0
 get_signal+0x1284/0x1330
 arch_do_signal_or_restart+0xbc/0x830
 exit_to_user_mode_loop+0x86/0x480
 do_syscall_64+0x2ad/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f928259acb9
Code: Unable to access opcode bytes at 0x7f928259ac8f.
RSP: 002b:00007f92833c20e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f9282815fa8 RCX: 00007f928259acb9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f9282815fa8
RBP: 00007f9282815fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9282816038 R14: 00007ffd576d3890 R15: 00007ffd576d3978
 </TASK>
