BUG: unable to handle kernel paging request in wait_consider_task

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 84f5ad46 Linux 4.14.162
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13edb149e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=2eeb394ad524f8c4
dashboard link: https://syzkaller.appspot.com/bug?extid=dc49a553cc0466ae3306
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+dc49a5...@syzkaller.appspotmail.com

kobject: 'tx-0' (ffff88805b6a7c98): kobject_add_internal: parent: 'queues',
set: 'queues'
kobject: 'tx-0' (ffff88805b6a7c98): kobject_uevent_env
kobject: 'tx-0' (ffff88805b6a7c98): fill_kobj_path: path
= '/devices/virtual/net/vcan27/queues/tx-0'
kobject: 'loop3' (ffff888096530a60): kobject_uevent_env
kobject: 'loop3' (ffff888096530a60): fill_kobj_path: path
= '/devices/virtual/block/loop3'
BUG: unable to handle kernel paging request at ffffffffffffff74
IP: wait_consider_task+0xa2/0x32a0 kernel/exit.c:1325
PGD 7e6d067 P4D 7e6d067 PUD 7e6f067 PMD 0
Oops: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 25832 Comm: syz-executor.5 Not tainted 4.14.162-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
task: ffff88805a244200 task.stack: ffff8880a9348000
RIP: 0010:wait_consider_task+0xa2/0x32a0 kernel/exit.c:1325
RSP: 0018:ffff8880a934fae8 EFLAGS: 00010246
RAX: 0000000000000007 RBX: fffffffffffffaf8 RCX: ffffffffffffff74
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880a934fcd8
RBP: ffff8880a934fbf0 R08: 0000000000000ec1 R09: ffffffff89574008
R10: ffff88805a244a80 R11: ffff88805a244200 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff8880a934fcd8 R15: ffff8880a934fcd8
FS: 0000000001da1940(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffff74 CR3: 000000005a013000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
do_wait_thread kernel/exit.c:1434 [inline]
do_wait+0x3ee/0x930 kernel/exit.c:1505
kernel_wait4+0x123/0x210 kernel/exit.c:1648
SYSC_wait4+0x106/0x110 kernel/exit.c:1660
SyS_wait4+0x2c/0x40 kernel/exit.c:1656
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x414d8a
RSP: 002b:00007fff4bb04aa8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: ffffffffffffffda RBX: 0000000000171c75 RCX: 0000000000414d8a
RDX: 0000000040000001 RSI: 00007fff4bb04ae0 RDI: ffffffffffffffff
RBP: 0000000000001adb R08: 0000000000000001 R09: 0000000001da1940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007fff4bb04ae0 R14: 0000000000171c2b R15: 00007fff4bb04af0
Code: 04 00 00 48 89 c8 48 89 8d 60 ff ff ff 48 c1 e8 03 42 0f b6 14 20 48
89 c8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 88 15 00 00 <44> 8b a3 7c
04 00 00 41 83 fc 10 0f 84 a3 00 00 00 e8 38 de 24
RIP: wait_consider_task+0xa2/0x32a0 kernel/exit.c:1325 RSP: ffff8880a934fae8
CR2: ffffffffffffff74
---[ end trace f1182e2875c276ff ]---


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.