Re: [syzbot] [kvm?] WARNING in kvm_recalculate_apic_map

[Sean Christopherson]

On Mon, Jul 08, 2024, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    f3a2439f20d9 Merge tag 'rproc-v6.3' of git://git.kernel.or..
> git tree:       upstream
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=12e2d518c80000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=81f5afa0c201c8de
> dashboard link: https://syzkaller.appspot.com/bug?extid=545f1326f405db4e1c3e
> compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=16b7be60c80000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11a380a8c80000
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/0719d575f3ac/disk-f3a2439f.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/4176aabb67b5/vmlinux-f3a2439f.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/2b0e3c0ab205/bzImage-f3a2439f.xz
> 
> The issue was bisected to:
> 
> commit 76e527509d37a15ff1714ddd003384f5f25fd3fc
> Author: Sean Christopherson <seanjc@xxxxxxxxxx>
> Date:   Fri Jan 6 01:12:52 2023 +0000
> 
>     KVM: x86: Skip redundant x2APIC logical mode optimized cluster setup
> 
> bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=124fbe60c80000
> final oops:     https://syzkaller.appspot.com/x/report.txt?x=114fbe60c80000
> console output: https://syzkaller.appspot.com/x/log.txt?x=164fbe60c80000
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+545f1326f405db4e1c3e@xxxxxxxxxxxxxxxxxxxxxxxxx
> Fixes: 76e527509d37 ("KVM: x86: Skip redundant x2APIC logical mode optimized cluster setup")

Known bug, I see if my random thought from that thread actually fixes the issue.

https://lkml.kernel.org/r/20240126161633.62529-1-haoyuwu254%40gmail.com