WARNING: can't dereference registers at (null) for ip apic_timer_interrupt

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e23d55af0e1f Linux 4.19.205
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1648e23e300000
kernel config: https://syzkaller.appspot.com/x/.config?x=2221dd564152b412
dashboard link: https://syzkaller.appspot.com/bug?extid=88d4d6a41bd12a37ad76
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

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+88d4d6...@syzkaller.appspotmail.com

WARNING: can't dereference registers at (null) for ip apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894


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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: e23d55af0e1f Linux 4.19.205
git tree: linux-4.19.y

console output: https://syzkaller.appspot.com/x/log.txt?x=1781dd4d300000

kernel config: https://syzkaller.appspot.com/x/.config?x=2221dd564152b412
dashboard link: https://syzkaller.appspot.com/bug?extid=88d4d6a41bd12a37ad76
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1349c82e300000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11593215300000