On Thu, 2022-05-12 at 21:27 +0000, Sean Christopherson wrote: > On Thu, May 12, 2022, Paolo Bonzini wrote: > > On 5/12/22 12:14, Maxim Levitsky wrote: > > > Yes, this is the root cause of the TDP mmu leak I was doing debug of in the last week. > > > Non working cmpxchg on which TDP mmu relies makes it install two differnt shadow pages > > > under same spte. > > > > Awesome! And queued, thanks. > > If you haven't done so already, can you add > > Cc: stable@xxxxxxxxxxxxxxx When I posted my patch, I checked that the patch didn't reach mainline yet, so I assumed that it won't be in -stable either yet, although it was CCed there. > > Also, given that we have concrete proof that not honoring atomic accesses can have > dire consequences for the guest, what about adding a capability to turn the emul_write > path into an emulation error? > This is a good idea. It might though break some guests - I did see that warning few times, that is why I wasn't alert by the fact that it started showing up more often. I'll take a look at this soon. Best regards, Maxim Levitsky
