1 files changed, 10 insertions, 3 deletions

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 4937e11f971a..b23ecc04ca51 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -226,6 +226,8 @@ struct vmcs {
 struct vmcs_host_state {
         unsigned long cr3;      /* May not match real cr3 */
         unsigned long cr4;      /* May not match real cr4 */
+        unsigned long gs_base;
+        unsigned long fs_base;
 
         u16           fs_sel, gs_sel, ldt_sel;
 #ifdef CONFIG_X86_64
@@ -2731,9 +2733,14 @@ static void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
                         vmcs_write16(HOST_GS_SELECTOR, 0);
                 host_state->gs_sel = gs_sel;
         }
-
-        vmcs_writel(HOST_FS_BASE, fs_base);
-        vmcs_writel(HOST_GS_BASE, gs_base);
+        if (unlikely(fs_base != host_state->fs_base)) {
+                vmcs_writel(HOST_FS_BASE, fs_base);
+                host_state->fs_base = fs_base;
+        }
+        if (unlikely(gs_base != host_state->gs_base)) {
+                vmcs_writel(HOST_GS_BASE, gs_base);
+                host_state->gs_base = gs_base;
+        }
 
         for (i = 0; i < vmx->save_nmsrs; ++i)
                 kvm_set_shared_msr(vmx->guest_msrs[i].index,