| Message ID | 20200317045238.30434-5-sean.j.christopherson@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: x86: TLB flushing fixes and enhancements | expand |
On Mon, Mar 16, 2020 at 09:52:10PM -0700, Sean Christopherson wrote: > From: Junaid Shahid <junaids@google.com> > > Free all L2 (guest_mmu) roots when emulating INVVPID for L1 and EPT is > disabled, as outstanding changes to the page tables managed by L1 need > to be recognized. > > Similar to handle_invpcid() and handle_invept(), rely on > kvm_mmu_free_roots() to do a remote TLB flush if necessary, e.g. if L1 > has never entered L2 then there is nothing to be done. > > Fixes: 5c614b3583e7b ("KVM: nVMX: nested VPID emulation") > Signed-off-by: Junaid Shahid <junaids@google.com> > [sean: ported to upstream KVM, reworded the comment and changelog] > Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> > --- > arch/x86/kvm/vmx/nested.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c > index 9624cea4ed9f..50bb7d8862aa 100644 > --- a/arch/x86/kvm/vmx/nested.c > +++ b/arch/x86/kvm/vmx/nested.c > @@ -5250,6 +5250,17 @@ static int handle_invvpid(struct kvm_vcpu *vcpu) > return kvm_skip_emulated_instruction(vcpu); > } > > + /* > + * Sync L2's shadow page tables if EPT is disabled, L1 is effectively > + * invalidating linear mappings for L2 (tagged with L2's VPID). Sync > + * all roots as VPIDs are not tracked in the MMU role. > + * > + * TODO: sync only the affected SPTEs for INVDIVIDUAL_ADDR. > + */ > + if (!enable_ept) > + kvm_mmu_free_roots(vcpu, &vcpu->arch.guest_mmu, Aha! This is wrong. guest_mmu is only used if EPT is enabled. The silver lining is that I have confirmed that this code is needed and works as intended (when the correct mmu is nuked). > + KVM_MMU_ROOTS_ALL); > + > return nested_vmx_succeed(vcpu); > } > > -- > 2.24.1 >
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 9624cea4ed9f..50bb7d8862aa 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -5250,6 +5250,17 @@ static int handle_invvpid(struct kvm_vcpu *vcpu) return kvm_skip_emulated_instruction(vcpu); } + /* + * Sync L2's shadow page tables if EPT is disabled, L1 is effectively + * invalidating linear mappings for L2 (tagged with L2's VPID). Sync + * all roots as VPIDs are not tracked in the MMU role. + * + * TODO: sync only the affected SPTEs for INVDIVIDUAL_ADDR. + */ + if (!enable_ept) + kvm_mmu_free_roots(vcpu, &vcpu->arch.guest_mmu, + KVM_MMU_ROOTS_ALL); + return nested_vmx_succeed(vcpu); }