Re: WARNING in vcpu_enter_guest

[syzbot]

syzbot has bisected this bug to:

commit 9446e6fce0ab9dfd44b96f630b4e3a0a0ab879fd
Author: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Date:   Wed Feb 12 12:27:10 2020 +0000

    KVM: x86: fix WARN_ON check of an unsigned less than zero

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=1744891de00000
start commit:   5076190d mm: slub: be more careful about the double cmpxch..
git tree:       upstream
final crash:    https://syzkaller.appspot.com/x/report.txt?x=14c4891de00000
console output: https://syzkaller.appspot.com/x/log.txt?x=10c4891de00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9f894bd92023de02
dashboard link: https://syzkaller.appspot.com/bug?extid=00be5da1d75f1cc95f6b
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=10bb4023e00000

Reported-by: syzbot+00be5da1d75f1cc95f6b@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 9446e6fce0ab ("KVM: x86: fix WARN_ON check of an unsigned less than zero")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection