INFO: task syz-executor465:6875 blocked for more than 143 seconds.
      Not tainted 5.9.0-rc3-next-20200903-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor465 state:D stack:28104 pid: 6875 ppid:  6869 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3777 [inline]
 __schedule+0xea9/0x2230 kernel/sched/core.c:4526
 schedule+0xd0/0x2a0 kernel/sched/core.c:4601
 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1855
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x163/0x260 kernel/sched/completion.c:138
 io_sq_thread_stop fs/io_uring.c:6906 [inline]
 io_finish_async fs/io_uring.c:6920 [inline]
 io_sq_offload_create fs/io_uring.c:7595 [inline]
 io_uring_create fs/io_uring.c:8671 [inline]
 io_uring_setup+0x1495/0x29a0 fs/io_uring.c:8744
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x440229
Code: Bad RIP value.
RSP: 002b:00007fff156e8618 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440229
RDX: 0000000000400ad0 RSI: 0000000020000000 RDI: 00000000000079dd
RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000401a30
R13: 0000000000401ac0 R14: 0000000000000000 R15: 0000000000000000
INFO: task io_uring-sq:6876 blocked for more than 143 seconds.
      Not tainted 5.9.0-rc3-next-20200903-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:io_uring-sq     state:D stack:31200 pid: 6876 ppid:     2 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3777 [inline]
 __schedule+0xea9/0x2230 kernel/sched/core.c:4526
 schedule+0xd0/0x2a0 kernel/sched/core.c:4601
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4660
 kthread+0x2ac/0x4a0 kernel/kthread.c:285
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Showing all locks held in the system:
1 lock held by khungtaskd/1173:
 #0: ffffffff89c67500 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5829
1 lock held by in:imklog/6552:
 #0: ffff88809708e0f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930

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

NMI backtrace for cpu 0
CPU: 0 PID: 1173 Comm: khungtaskd Not tainted 5.9.0-rc3-next-20200903-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x198/0x1fd lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline]
 watchdog+0xd89/0xf30 kernel/hung_task.c:339
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3911 Comm: systemd-journal Not tainted 5.9.0-rc3-next-20200903-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:format_decode+0x1dc/0xad0 lib/vsprintf.c:2370
Code: 44 24 38 c6 45 04 00 48 89 04 24 e8 de 45 be fd 48 8b 04 24 48 b9 00 00 00 00 00 fc ff df 4c 8d 60 01 4c 89 e0 4c 89 64 24 38 <4c> 89 e2 48 c1 e8 03 83 e2 07 0f b6 04 08 38 d0 7f 08 84 c0 0f 85
RSP: 0018:ffffc90005527a10 EFLAGS: 00000093
RAX: ffffffff884c6661 RBX: ffffffff884c6660 RCX: dffffc0000000000
RDX: ffff888092cc8080 RSI: ffffffff83b69d22 RDI: 0000000000000001
RBP: ffffc90005527b28 R08: 0000000000000610 R09: 0000000024c1aca4
R10: 0000000000000025 R11: 0000000000000000 R12: ffffffff884c6661
R13: ffffffff884c6660 R14: 1ffff92000aa4f45 R15: 0000000000000025
FS:  00007f9dcd4d58c0(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9dca879000 CR3: 00000000a920d000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 vsnprintf+0x155/0x14f0 lib/vsprintf.c:2570
 vscnprintf lib/vsprintf.c:2721 [inline]
 scnprintf+0xbb/0x140 lib/vsprintf.c:2775
 info_print_ext_header.constprop.0+0x1e2/0x270 kernel/printk/printk.c:605
 devkmsg_read+0x436/0xa50 kernel/printk/printk.c:786
 vfs_read+0x1df/0x5a0 fs/read_write.c:479
 ksys_read+0x12d/0x250 fs/read_write.c:607
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f9dcca65210
Code: 73 01 c3 48 8b 0d 98 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 c1 20 00 00 75 10 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 4e fc ff ff 48 89 04 24
RSP: 002b:00007ffe3cc12ac8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007ffe3cc15540 RCX: 00007f9dcca65210
RDX: 0000000000002000 RSI: 00007ffe3cc13340 RDI: 0000000000000009
RBP: 0000000000000000 R08: 0000000000000008 R09: 00007ffe3cd630f0
R10: 000000000001b726 R11: 0000000000000246 R12: 00007ffe3cc13340
R13: 00007ffe3cc15498 R14: 000055f127e54958 R15: 0005ae7a517917cf