BUG: unable to handle kernel paging request in check_preempt_wakeup

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 903b77c63167 Merge tag 'linux-kselftest-4.21-rc1' of git:/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=105658e7400000
kernel config: https://syzkaller.appspot.com/x/.config?x=53a2f2aa0b1f7606
dashboard link: https://syzkaller.appspot.com/bug?extid=b0483343ade2f0865c48
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
userspace arch: i386
CC: [linux-...@vger.kernel.org tg...@linutronix.de]

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+b04833...@syzkaller.appspotmail.com


BUG: unable to handle kernel paging request at ffffdd42000000c4
#PF error: [normal kernel read fault]
PGD 0 P4D 0
Thread overran stack, or stack corrupted
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: -2124138558 Comm: Not tainted 4.20.0+ #298
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:check_preempt_wakeup+0x193/0x1280 kernel/sched/fair.c:6819
Code: c1 eb 03 41 80 3c 03 00 0f 85 29 0b 00 00 4c 8b ba d8 01 00 00 48 b8
00 00 00 00 00 fc ff df 49 8d 7f 18 49 89 fb 49 c1 eb 03 <41> 0f b6 04 03
84 c0 74 08 3c 03 0f 8e 40 0a 00 00 41 8b 47 18 48
RSP: 0018:ffff8880ae707678 EFLAGS: 00010802
RAX: dffffc0000000000 RBX: ffff88808dc820c0 RCX: ffff8880ae72ce00
RDX: ffff8880a947e440 RSI: ffff88808dc82040 RDI: ffff0a1000000621
RBP: ffff8880ae707778 R08: ffff8880ae7076d0 R09: ffff8880ae707710
R10: ffff8880ae72cec0 R11: 1fffe142000000c4 R12: ffff8880a947e4c0
R13: ffff8880ae707750 R14: 1ffff11015ce0ed6 R15: ffff0a1000000609
FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffdd42000000c4 CR3: 000000005d248000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
check_preempt_curr+0x1ec/0x3a0 kernel/sched/core.c:846
ttwu_do_wakeup+0x8a/0x6f0 kernel/sched/core.c:1657
ttwu_do_activate+0x146/0x1f0 kernel/sched/core.c:1703
ttwu_queue kernel/sched/core.c:1847 [inline]
try_to_wake_up+0x9a3/0x1460 kernel/sched/core.c:2057
wake_up_process+0x10/0x20 kernel/sched/core.c:2129
hrtimer_wakeup+0x48/0x60 kernel/time/hrtimer.c:1637
__run_hrtimer kernel/time/hrtimer.c:1389 [inline]
__hrtimer_run_queues+0x41c/0x10d0 kernel/time/hrtimer.c:1451
hrtimer_interrupt+0x313/0x780 kernel/time/hrtimer.c:1509
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1035 [inline]
smp_apic_timer_interrupt+0x1a1/0x760 arch/x86/kernel/apic/apic.c:1060
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
</IRQ>
Modules linked in:
CR2: ffffdd42000000c4
---[ end trace 30948c938efa3e24 ]---
RIP: 0010:check_preempt_wakeup+0x193/0x1280 kernel/sched/fair.c:6819
Code: c1 eb 03 41 80 3c 03 00 0f 85 29 0b 00 00 4c 8b ba d8 01 00 00 48 b8
00 00 00 00 00 fc ff df 49 8d 7f 18 49 89 fb 49 c1 eb 03 <41> 0f b6 04 03
84 c0 74 08 3c 03 0f 8e 40 0a 00 00 41 8b 47 18 48
RSP: 0018:ffff8880ae707678 EFLAGS: 00010802
RAX: dffffc0000000000 RBX: ffff88808dc820c0 RCX: ffff8880ae72ce00
RDX: ffff8880a947e440 RSI: ffff88808dc82040 RDI: ffff0a1000000621
RBP: ffff8880ae707778 R08: ffff8880ae7076d0 R09: ffff8880ae707710
R10: ffff8880ae72cec0 R11: 1fffe142000000c4 R12: ffff8880a947e4c0
R13: ffff8880ae707750 R14: 1ffff11015ce0ed6 R15: ffff0a1000000609
FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffdd42000000c4 CR3: 000000005d248000 CR4: 00000000001426e0
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.