[PATCH] kvm: vmx: Don't use INVVPID when EPT is enabled

From: Jim Mattson <jmattson@google.com>
To: kvm@vger.kernel.org
Cc: Jim Mattson <jmattson@google.com>
Subject: [PATCH] kvm: vmx: Don't use INVVPID when EPT is enabled
Date: Wed, 15 Mar 2017 07:56:11 -0700	[thread overview]
Message-ID: <20170315145611.16880-1-jmattson@google.com> (raw)

According to the Intel SDM, volume 3, section 28.3.2: Creating and
Using Cached Translation Information, "No linear mappings are used
while EPT is in use." INVEPT will invalidate both the guest-physical
mappings and the combined mappings in the TLBs and paging-structure
caches, so an INVVPID is superfluous.

Signed-off-by: Jim Mattson <jmattson@google.com>
---
 arch/x86/kvm/vmx.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 2c21181c8a70..114f358b959c 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -4011,11 +4011,12 @@ static void exit_lmode(struct kvm_vcpu *vcpu)
 
 static inline void __vmx_flush_tlb(struct kvm_vcpu *vcpu, int vpid)
 {
-	vpid_sync_context(vpid);
 	if (enable_ept) {
 		if (!VALID_PAGE(vcpu->arch.mmu.root_hpa))
 			return;
 		ept_sync_context(construct_eptp(vcpu->arch.mmu.root_hpa));
+	} else {
+		vpid_sync_context(vpid);
 	}
 }
 
-- 
2.12.0.367.g23dc2f6d3c-goog
