BUG: unable to handle kernel paging request in wait_consider_task

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: dda0e292 Linux 4.19.114
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1790e3b3e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=f32ac7e5b2d5c341
dashboard link: https://syzkaller.appspot.com/bug?extid=d2dffb997b77c916497d
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+d2dffb...@syzkaller.appspotmail.com

input: syz1 as /devices/virtual/input/input342
bridge1: port 1(vlan2) entered blocking state
bridge1: port 1(vlan2) entered disabled state
BUG: unable to handle kernel paging request at ffff88800056a4ac
PGD c401067 P4D c401067 PUD c402067 PMD 134063 PTE 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 6661 Comm: syz-executor.2 Not tainted 4.19.114-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:193 [inline]
RIP: 0010:wait_consider_task+0xad/0x35a0 kernel/exit.c:1349
Code: 6c 04 00 00 48 89 c8 48 89 4c 24 08 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 58 19 00 00 <44> 8b a5 6c 04 00 00 bf 10 00 00 00 44 89 e6 e8 1f 23 2a 00 41 83
RSP: 0018:ffff88808fc67af8 EFLAGS: 00010246
RAX: 0000000000000007 RBX: 0000000000000000 RCX: ffff88800056a4ac
RDX: 0000000000000000 RSI: ffffffff813d8280 RDI: ffff88808fc67cf8
RBP: ffff88800056a040 R08: ffff888090bea3c0 R09: fffffbfff1141219
R10: fffffbfff1141218 R11: ffffffff88a090c3 R12: dffffc0000000000
R13: ffff88800056a040 R14: 0000000000000000 R15: ffff88808fc67cf8
FS: 0000000002b97940(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff88800056a4ac CR3: 000000008c93c000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
do_wait_thread kernel/exit.c:1458 [inline]
do_wait+0x429/0x9c0 kernel/exit.c:1529
kernel_wait4+0x14c/0x260 kernel/exit.c:1672
__do_sys_wait4+0x147/0x160 kernel/exit.c:1684
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4166ca
Code: 0f 83 6a 18 00 00 c3 66 0f 1f 84 00 00 00 00 00 8b 05 ce 1d 87 00 85 c0 75 36 45 31 d2 48 63 d2 48 63 ff b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 d4 ff ff ff f7
RSP: 002b:00007ffd1c8f12f8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: ffffffffffffffda RBX: 00000000000b028b RCX: 00000000004166ca
RDX: 0000000040000001 RSI: 00007ffd1c8f1330 RDI: ffffffffffffffff
RBP: 0000000000000834 R08: 0000000000000001 R09: 0000000002b97940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 00007ffd1c8f1330 R14: 00000000000b0233 R15: 00007ffd1c8f1340
Modules linked in:
CR2: ffff88800056a4ac
---[ end trace c74362784fa8fd9e ]---
BUG: unable to handle kernel paging request at ffff888000400000
RIP: 0010:__read_once_size include/linux/compiler.h:193 [inline]
RIP: 0010:wait_consider_task+0xad/0x35a0 kernel/exit.c:1349
PGD c401067
Code: 6c 04 00 00 48 89 c8 48 89 4c 24 08 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 58 19 00 00 <44> 8b a5 6c 04 00 00 bf 10 00 00 00 44 89 e6 e8 1f 23 2a 00 41 83
P4D c401067
RSP: 0018:ffff88808fc67af8 EFLAGS: 00010246
PUD c402067
PMD 134063
RAX: 0000000000000007 RBX: 0000000000000000 RCX: ffff88800056a4ac
PTE 0
RDX: 0000000000000000 RSI: ffffffff813d8280 RDI: ffff88808fc67cf8
RBP: ffff88800056a040 R08: ffff888090bea3c0 R09: fffffbfff1141219
Oops: 0002 [#2] PREEMPT SMP KASAN
R10: fffffbfff1141218 R11: ffffffff88a090c3 R12: dffffc0000000000
CPU: 1 PID: 1336 Comm: syz-executor.2 Tainted: G D 4.19.114-syzkaller #0
R13: ffff88800056a040 R14: 0000000000000000 R15: ffff88808fc67cf8
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
FS: 0000000002b97940(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
RIP: 0010:__writeq arch/x86/include/asm/io.h:100 [inline]
RIP: 0010:bitfill_aligned drivers/video/fbdev/core/cfbfillrect.c:64 [inline]
RIP: 0010:bitfill_aligned+0xfc/0x200 drivers/video/fbdev/core/cfbfillrect.c:35
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Code: fd 44 89 e0 31 d2 bf 07 00 00 00 f7 f5 41 89 c4 89 c6 89 c5 e8 25 80 f1 fd 41 83 fc 07 76 62 45 89 e7 4c 89 ed e8 a4 7e f1 fd <48> 89 5d 00 48 89 5d 08 48 89 5d 10 48 89 5d 18 48 89 5d 20 48 89
CR2: ffff88800056a4ac CR3: 000000008c93c000 CR4: 00000000001406f0
RSP: 0018:ffff8880951371a8 EFLAGS: 00010246
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
RAX: 0000000000040000 RBX: 0000000000000000 RCX: ffffc90009ede000


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[syzbot]

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