KVM/VMX: Change hv flush logic when ept tables are mismatched.

If ept table pointers are mismatched, flushing tlb for each vcpus via
hv flush interface still helps to reduce vmexits which are triggered
by IPI and INEPT emulation.

Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 0050fe81d8571ba16bc29264ff7c6ac4afca67e6..a9ed7a723a0c4d215e919db3c33596c6b37053cb 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1571,7 +1571,8 @@ static void check_ept_pointer_match(struct kvm *kvm)
 
 static int vmx_hv_remote_flush_tlb(struct kvm *kvm)
 {
-       int ret;
+       struct kvm_vcpu *vcpu;
+       int ret = -ENOTSUPP, i;
 
        spin_lock(&to_kvm_vmx(kvm)->ept_pointer_lock);
 
@@ -1579,14 +1580,14 @@ static int vmx_hv_remote_flush_tlb(struct kvm *kvm)
                check_ept_pointer_match(kvm);
 
        if (to_kvm_vmx(kvm)->ept_pointers_match != EPT_POINTERS_MATCH) {
-               ret = -ENOTSUPP;
-               goto out;
+               kvm_for_each_vcpu(i, vcpu, kvm)
+                       ret |= hyperv_flush_guest_mapping(
+                               to_vmx(kvm_get_vcpu(kvm, i))->ept_pointer);
+       } else {
+               ret = hyperv_flush_guest_mapping(
+                               to_vmx(kvm_get_vcpu(kvm, 0))->ept_pointer);
        }
 
-       ret = hyperv_flush_guest_mapping(
-                       to_vmx(kvm_get_vcpu(kvm, 0))->ept_pointer);
-
-out:
        spin_unlock(&to_kvm_vmx(kvm)->ept_pointer_lock);
        return ret;
 }