Re: general protection fault in __schedule (2)

From: Sean Christopherson
Date: Fri Nov 22 2019 - 15:54:56 EST


On Thu, Nov 21, 2019 at 11:19:00PM -0800, syzbot wrote:
> syzbot has bisected this bug to:
>
> commit 8fcc4b5923af5de58b80b53a069453b135693304
> Author: Jim Mattson <jmattson@xxxxxxxxxx>
> Date: Tue Jul 10 09:27:20 2018 +0000
>
> kvm: nVMX: Introduce KVM_CAP_NESTED_STATE
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=124cdbace00000
> start commit: 234b69e3 ocfs2: fix ocfs2 read block panic
> git tree: upstream
> final crash: https://syzkaller.appspot.com/x/report.txt?x=114cdbace00000
> console output: https://syzkaller.appspot.com/x/log.txt?x=164cdbace00000
> kernel config: https://syzkaller.appspot.com/x/.config?x=5fa12be50bca08d8
> dashboard link: https://syzkaller.appspot.com/bug?extid=7e2ab84953e4084a638d
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=150f0a4e400000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17f67111400000
>
> Reported-by: syzbot+7e2ab84953e4084a638d@xxxxxxxxxxxxxxxxxxxxxxxxx
> Fixes: 8fcc4b5923af ("kvm: nVMX: Introduce KVM_CAP_NESTED_STATE")
>
> For information about bisection process see: https://goo.gl/tpsmEJ#bisection

Is there a way to have syzbot stop processing/bisecting these things
after a reasonable amount of time? The original crash is from August of
last year...

Note, the original crash is actually due to KVM's put_kvm() fd race, but
whatever we want to blame, it's a duplicate.

#syz dup: general protection fault in kvm_lapic_hv_timer_in_use