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Diffstat (limited to 'arch/x86/kvm/vmx/vmx.h')
-rw-r--r--arch/x86/kvm/vmx/vmx.h18
1 files changed, 18 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index a3da84f4ea45..e2b04f4c0fef 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -640,6 +640,24 @@ BUILD_CONTROLS_SHADOW(tertiary_exec, TERTIARY_VM_EXEC_CONTROL, 64)
(1 << VCPU_EXREG_EXIT_INFO_1) | \
(1 << VCPU_EXREG_EXIT_INFO_2))
+static inline unsigned long vmx_l1_guest_owned_cr0_bits(void)
+{
+ unsigned long bits = KVM_POSSIBLE_CR0_GUEST_BITS;
+
+ /*
+ * CR0.WP needs to be intercepted when KVM is shadowing legacy paging
+ * in order to construct shadow PTEs with the correct protections.
+ * Note! CR0.WP technically can be passed through to the guest if
+ * paging is disabled, but checking CR0.PG would generate a cyclical
+ * dependency of sorts due to forcing the caller to ensure CR0 holds
+ * the correct value prior to determining which CR0 bits can be owned
+ * by L1. Keep it simple and limit the optimization to EPT.
+ */
+ if (!enable_ept)
+ bits &= ~X86_CR0_WP;
+ return bits;
+}
+
static inline struct kvm_vmx *to_kvm_vmx(struct kvm *kvm)
{
return container_of(kvm, struct kvm_vmx, kvm);