On 04/12/20 01:43, Sean Christopherson wrote:
On Thu, Dec 03, 2020, Rick Edgecombe wrote:In the TDP MMU, use shadow_phys_bits to dermine the maximum possible GFN mapped in the guest for zapping operations. boot_cpu_data.x86_phys_bits may be reduced in the case of HW features that steal HPA bits for other purposes. However, this doesn't necessarily reduce GPA space that can be accessed via TDP. So zap based on a maximum gfn calculated with MAXPHYADDR retrieved from CPUID. This is already stored in shadow_phys_bits, so use it instead of x86_phys_bits. Fixes: faaf05b00aec ("kvm: x86/mmu: Support zapping SPTEs in the TDP MMU") Signed-off-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>Dang, in hindsight it'd be nice if KVM_CAP_SMALLER_MAXPHYADDR allowed explicitly setting the max MAXPHYADDR for an entire VM instead of being a simple toggle. E.g. TDX and SEV-ES likely could also make use of "what's this VM's max GPA?". Reviewed-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Queued, thanks. Paolo
