BUG: unable to handle kernel paging request in run_timer_softirq (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 63623fd4 Merge tag 'for-linus' of git://git.kernel.org/pub..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13b2ac55e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9833e26bab355358
dashboard link: https://syzkaller.appspot.com/bug?extid=1621ef7d2ccfa3595b13
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
CC: [b...@alien8.de h...@zytor.com linux-...@vger.kernel.org mi...@redhat.com pet...@infradead.org tg...@linutronix.de x...@kernel.org]

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+1621ef...@syzkaller.appspotmail.com

BUG: unable to handle page fault for address: ffff88821880a1d8
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD c601067 P4D c601067 PUD c604067 PMD eea063 PTE 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:lookup_object lib/debugobjects.c:197 [inline]
RIP: 0010:debug_object_deactivate lib/debugobjects.c:712 [inline]
RIP: 0010:debug_object_deactivate+0x175/0x320 lib/debugobjects.c:698
Code: 01 00 00 4d 8b 24 24 4d 85 e4 0f 84 83 00 00 00 49 8d 7c 24 18 83 c3 01 48 89 fa 48 c1 ea 03 42 80 3c 2a 00 0f 85 26 01 00 00 <4d> 3b 7c 24 18 75 c0 49 8d 7c 24 10 48 b8 00 00 00 00 00 fc ff df
RSP: 0018:ffffc90000da8cf0 EFLAGS: 00010046
RAX: 1ffffffff174dfa0 RBX: 000000000000000a RCX: ffffffff815c2ec9
RDX: 1ffff1104310143b RSI: 0000000000000082 RDI: ffff88821880a1d8
RBP: ffffc90000da8dd8 R08: 0000000000000004 R09: ffffffff8ba6fd08
R10: fffff520001b518a R11: 0000000000000003 R12: ffff88821880a1c0
R13: dffffc0000000000 R14: 1ffff920001b51a2 R15: ffffffff8c3ae180
FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff88821880a1d8 CR3: 000000004d241000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
debug_timer_deactivate kernel/time/timer.c:719 [inline]
debug_deactivate kernel/time/timer.c:768 [inline]
detach_timer kernel/time/timer.c:813 [inline]
expire_timers kernel/time/timer.c:1438 [inline]
__run_timers kernel/time/timer.c:1773 [inline]
__run_timers kernel/time/timer.c:1740 [inline]
run_timer_softirq+0x520/0x1790 kernel/time/timer.c:1786
__do_softirq+0x262/0x98c kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x19b/0x1e0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:546 [inline]
smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1146
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
</IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: c8 c3 c3 f9 eb 8a cc cc cc cc cc cc e9 07 00 00 00 0f 00 2d 94 05 58 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 84 05 58 00 fb f4 <c3> cc 55 48 89 e5 41 57 41 56 41 55 41 54 53 e8 5e 83 72 f9 e8 c9
RSP: 0018:ffffc90000d3fd68 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff136763a RBX: ffff8880a99fc340 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffff8880a99fcbd4
RBP: ffffc90000d3fd98 R08: ffff8880a99fc340 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
R13: ffffffff8aa5b4c0 R14: 0000000000000000 R15: 0000000000000001
arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:686
default_idle_call+0x84/0xb0 kernel/sched/idle.c:94
cpuidle_idle_call kernel/sched/idle.c:154 [inline]
do_idle+0x3c8/0x6e0 kernel/sched/idle.c:269
cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:361
start_secondary+0x2f4/0x410 arch/x86/kernel/smpboot.c:264
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242
Modules linked in:
CR2: ffff88821880a1d8
---[ end trace 691cc0d0b1c7afc0 ]---
RIP: 0010:lookup_object lib/debugobjects.c:197 [inline]
RIP: 0010:debug_object_deactivate lib/debugobjects.c:712 [inline]
RIP: 0010:debug_object_deactivate+0x175/0x320 lib/debugobjects.c:698
Code: 01 00 00 4d 8b 24 24 4d 85 e4 0f 84 83 00 00 00 49 8d 7c 24 18 83 c3 01 48 89 fa 48 c1 ea 03 42 80 3c 2a 00 0f 85 26 01 00 00 <4d> 3b 7c 24 18 75 c0 49 8d 7c 24 10 48 b8 00 00 00 00 00 fc ff df
RSP: 0018:ffffc90000da8cf0 EFLAGS: 00010046
RAX: 1ffffffff174dfa0 RBX: 000000000000000a RCX: ffffffff815c2ec9
RDX: 1ffff1104310143b RSI: 0000000000000082 RDI: ffff88821880a1d8
RBP: ffffc90000da8dd8 R08: 0000000000000004 R09: ffffffff8ba6fd08
R10: fffff520001b518a R11: 0000000000000003 R12: ffff88821880a1c0
R13: dffffc0000000000 R14: 1ffff920001b51a2 R15: ffffffff8c3ae180
FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff88821880a1d8 CR3: 000000004d241000 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.