BUG: unable to handle kernel paging request in watchdog

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 13af6c74 Linux 4.19.136
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1594d3d4900000
kernel config: https://syzkaller.appspot.com/x/.config?x=5b7578d3b5457a49
dashboard link: https://syzkaller.appspot.com/bug?extid=7889bf48e7a394421527
compiler: gcc (GCC) 10.1.0-syz 20200507

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7889bf...@syzkaller.appspotmail.com

BUG: unable to handle kernel paging request at fffffffffffffa80
PGD 8c70067 P4D 8c70067 PUD 8c72067 PMD 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 1089 Comm: khungtaskd Not tainted 4.19.136-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
RIP: 0010:watchdog+0x31b/0xe60 kernel/hung_task.c:287
Code: ff 45 85 ff 0f 85 b7 00 00 00 e9 ec 05 00 00 e8 6b f5 ff ff 48 8d 7b 10 48 89 f8 48 c1 e8 03 42 80 3c 30 00 0f 85 c5 09 00 00 <4c> 8b 63 10 bf 02 00 00 00 4c 89 e6 e8 d4 f6 ff ff 49 83 fc 02 0f
RSP: 0018:ffff8880a795fea0 EFLAGS: 00010246
RAX: 1fffffffffffff50 RBX: fffffffffffffa70 RCX: ffffffff8169babc
RDX: 0000000000000000 RSI: ffffffff8169b9d5 RDI: fffffffffffffa80
RBP: 00000000003ff7e3 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000000 R12: 000000000000000a
R13: 0000000100025300 R14: dffffc0000000000 R15: 00000000003ff7e4
FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffa80 CR3: 00000000511b3000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
kthread+0x30b/0x410 kernel/kthread.c:246
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Modules linked in:
CR2: fffffffffffffa80
---[ end trace 24e9967ace673255 ]---
RIP: 0010:check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
RIP: 0010:watchdog+0x31b/0xe60 kernel/hung_task.c:287
Code: ff 45 85 ff 0f 85 b7 00 00 00 e9 ec 05 00 00 e8 6b f5 ff ff 48 8d 7b 10 48 89 f8 48 c1 e8 03 42 80 3c 30 00 0f 85 c5 09 00 00 <4c> 8b 63 10 bf 02 00 00 00 4c 89 e6 e8 d4 f6 ff ff 49 83 fc 02 0f
RSP: 0018:ffff8880a795fea0 EFLAGS: 00010246
RAX: 1fffffffffffff50 RBX: fffffffffffffa70 RCX: ffffffff8169babc
RDX: 0000000000000000 RSI: ffffffff8169b9d5 RDI: fffffffffffffa80
RBP: 00000000003ff7e3 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000000 R12: 000000000000000a
R13: 0000000100025300 R14: dffffc0000000000 R15: 00000000003ff7e4
FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffa80 CR3: 00000000511b3000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

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