On Tue, Dec 13, 2022 at 06:15:56PM +0000, Sean Christopherson wrote: > On Tue, Dec 13, 2022, David Matlack wrote: > > On Mon, Dec 12, 2022 at 7:30 PM Sean Christopherson <seanjc@xxxxxxxxxx> wrote: > > > > > > Don't install a leaf TDP MMU SPTE if the parent page's level doesn't > > > match the target level of the fault, and instead have the vCPU retry the > > > faulting instruction after warning. Continuing on is completely > > > unnecessary as the absolute worst case scenario of retrying is DoSing > > > the vCPU, whereas continuing on all but guarantees bigger explosions, e.g. > > > > Would it make sense to kill the VM instead via KVM_BUG()? > > No, because if bug that hits this escapes to a release, odds are quite high that > retrying will succeed. E.g. the fix earlier in this series is for a rare corner > case that I was able to hit consistently only by hacking KVM to effectively > synchronize the page fault and zap. Other than an extra page fault, no harm has > been done to the guest, e.g. there's no need to kill the VM to protect it from > data corruption. Good points, agreed!
