INFO: task syz.6.631:11146 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.631       state:D stack:26456 pid:11146 tgid:11143 ppid:9949   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x6ba/0x920
 down_read+0x9c/0x330
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x120/0x240
 drop_caches_sysctl_handler+0x97/0x170
 proc_sys_call_handler+0x4c6/0x830
 do_iter_readv_writev+0x612/0x8c0
 vfs_writev+0x343/0x990
 do_writev+0x154/0x2e0
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa93999ce59
RSP: 002b:00007fa937bb4028 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007fa939c16180 RCX: 00007fa93999ce59
RDX: 0000000000000001 RSI: 00002000000000c0 RDI: 0000000000000008
RBP: 00007fa939a32e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa939c16218 R14: 00007fa939c16180 R15: 00007ffce2992278
 </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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x380
 sys_info+0x135/0x170
 watchdog+0xfd7/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 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: 14219 Comm: syz.2.951 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:kasan_check_range+0x97/0x2c0
Code: 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 00 44 89 dd
RSP: 0000:ffffc9000707f658 EFLAGS: 00000246
RAX: fe0764401f986b01 RBX: fffffffffffffffe RCX: ffffffff84c2cdac
RDX: 0000000000000001 RSI: 0000000000000028 RDI: ffffc9000707f6f8
RBP: 0000000000000000 R08: ffffc9000707f71f R09: 1ffff92000e0fee3
R10: dffffc0000000000 R11: fffff52000e0fee2 R12: 0000000000000005
R13: 0000000000000000 R14: fffff52000e0fee4 R15: 1ffff92000e0fedf
FS:  00007f9235cc36c0(0000) GS:ffff88818dc2d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f93f55bd000 CR3: 0000000199e6a000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __asan_memset+0x22/0x50
 debug_check_no_obj_freed+0x4c/0x450
 kfree+0x13e/0x640
 fuse_perform_write+0xe57/0x1c60
 fuse_file_write_iter+0xd74/0x11a0
 vfs_write+0x612/0xba0
 ksys_write+0x150/0x270
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9234d9ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9235cc3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f9235015fa0 RCX: 00007f9234d9ce59
RDX: 0000000000000028 RSI: 0000200000000200 RDI: 000000000000000a
RBP: 00007f9234e32e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9235016038 R14: 00007f9235015fa0 R15: 00007ffce4533ce8
 </TASK>
