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

From: Sean Christopherson
Date: Fri Apr 21 2023 - 18:02:42 EST


On Fri, Apr 21, 2023, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: d3e1ee0e67e7 Add linux-next specific files for 20230421
> git tree: linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=16ac3de0280000
> kernel config: https://syzkaller.appspot.com/x/.config?x=53c789efbcc06cf6
> dashboard link: https://syzkaller.appspot.com/bug?extid=094a74444165dbcd3a54
> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
>
> Unfortunately, I don't have any reproducer for this issue yet.
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/c558a9e1fe6a/disk-d3e1ee0e.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/2ec100a34c4c/vmlinux-d3e1ee0e.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/1afcd9936dc1/bzImage-d3e1ee0e.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+094a74444165dbcd3a54@xxxxxxxxxxxxxxxxxxxxxxxxx

Time to see if syzbot gets confused by a fix that was squashed into the guilty
commit.

#syz fix: KVM: x86: Preserve TDP MMU roots until they are explicitly invalidated