KVM: nEPT: reset PDPTR register cache on nested vmentry emulation

After nested vmentry stale cache can be used to reload L2 PDPTR pointers
which will cause L2 guest to fail. Fix it by invalidating cache on nested
vmentry emulation.

https://bugzilla.kernel.org/show_bug.cgi?id=60830

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 1f1da43ff2a2ca66a137c434cf738dbf7a03e704..48735936860cc13d5beb0d9daa3ff1bdac6148a9 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -7766,6 +7766,10 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
                vmcs_write64(GUEST_PDPTR1, vmcs12->guest_pdptr1);
                vmcs_write64(GUEST_PDPTR2, vmcs12->guest_pdptr2);
                vmcs_write64(GUEST_PDPTR3, vmcs12->guest_pdptr3);
+               __clear_bit(VCPU_EXREG_PDPTR,
+                               (unsigned long *)&vcpu->arch.regs_avail);
+               __clear_bit(VCPU_EXREG_PDPTR,
+                               (unsigned long *)&vcpu->arch.regs_dirty);
        }
 
        kvm_register_write(vcpu, VCPU_REGS_RSP, vmcs12->guest_rsp);