[PATCH 1/2] KVM: x86: Fixup "Get active PCID only when writing a CR3 value"

[Sean Christopherson]

From: Sean Christopherson <sean.j.christopher...@intel.com>

Fix SME and PCID, which got horribly mangled on application.

Fixes: a16241ae56fa ("KVM: x86: Get active PCID only when writing a CR3 value")
Signed-off-by: Sean Christopherson <sean.j.christopher...@intel.com>
Signed-off-by: Sean Christopherson <sea...@google.com>
---
 arch/x86/kvm/svm/svm.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 7876ddf896b8..271196400495 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -3907,15 +3907,20 @@ static void svm_load_mmu_pgd(struct kvm_vcpu *vcpu, 
hpa_t root_hpa,
        struct vcpu_svm *svm = to_svm(vcpu);
        unsigned long cr3;
 
-       cr3 = __sme_set(root_hpa);
        if (npt_enabled) {
-               svm->vmcb->control.nested_cr3 = root_hpa;
+               svm->vmcb->control.nested_cr3 = __sme_set(root_hpa);
                vmcb_mark_dirty(svm->vmcb, VMCB_NPT);
 
                /* Loading L2's CR3 is handled by enter_svm_guest_mode.  */
                if (!test_bit(VCPU_EXREG_CR3, (ulong *)&vcpu->arch.regs_avail))
                        return;
                cr3 = vcpu->arch.cr3;
+       } else if (vcpu->arch.mmu->shadow_root_level >= PT64_ROOT_4LEVEL) {
+               cr3 = __sme_set(root_hpa) | kvm_get_active_pcid(vcpu);
+       } else {
+               /* PCID in the guest should be impossible with a 32-bit MMU. */
+               WARN_ON_ONCE(kvm_get_active_pcid(vcpu));
+               cr3 = root_hpa;
        }
 
        svm->vmcb->save.cr3 = cr3;
-- 
2.30.1.766.gb4fecdf3b7-goog