Re: [PATCH v3 04/11] KVM: VMX: Fold Hyper-V EPTP checking into it's only caller

From: Vitaly Kuznetsov
Date: Thu Nov 12 2020 - 05:41:47 EST


Sean Christopherson <sean.j.christopherson@xxxxxxxxx> writes:

> Fold check_ept_pointer_match() into hv_remote_flush_tlb_with_range() in
> preparation for combining the kvm_for_each_vcpu loops of the ==CHECK and
> !=MATCH statements.
>
> No functional change intended.
>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
> ---
> arch/x86/kvm/vmx/vmx.c | 44 +++++++++++++++++++-----------------------
> 1 file changed, 20 insertions(+), 24 deletions(-)
>
> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index a6442a861ffc..f5e9e2f61e10 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -472,28 +472,6 @@ static const u32 vmx_uret_msrs_list[] = {
> static bool __read_mostly enlightened_vmcs = true;
> module_param(enlightened_vmcs, bool, 0444);
>
> -/* check_ept_pointer() should be under protection of ept_pointer_lock. */
> -static void check_ept_pointer_match(struct kvm *kvm)
> -{
> - struct kvm_vcpu *vcpu;
> - u64 tmp_eptp = INVALID_PAGE;
> - int i;
> -
> - kvm_for_each_vcpu(i, vcpu, kvm) {
> - if (!VALID_PAGE(tmp_eptp)) {
> - tmp_eptp = to_vmx(vcpu)->ept_pointer;
> - } else if (tmp_eptp != to_vmx(vcpu)->ept_pointer) {
> - to_kvm_vmx(kvm)->hv_tlb_eptp = INVALID_PAGE;
> - to_kvm_vmx(kvm)->ept_pointers_match
> - = EPT_POINTERS_MISMATCH;
> - return;
> - }
> - }
> -
> - to_kvm_vmx(kvm)->hv_tlb_eptp = tmp_eptp;
> - to_kvm_vmx(kvm)->ept_pointers_match = EPT_POINTERS_MATCH;
> -}
> -
> static int kvm_fill_hv_flush_list_func(struct hv_guest_mapping_flush_list *flush,
> void *data)
> {
> @@ -523,11 +501,29 @@ static int hv_remote_flush_tlb_with_range(struct kvm *kvm,
> struct kvm_vmx *kvm_vmx = to_kvm_vmx(kvm);
> struct kvm_vcpu *vcpu;
> int ret = 0, i;
> + u64 tmp_eptp;
>
> spin_lock(&kvm_vmx->ept_pointer_lock);
>
> - if (kvm_vmx->ept_pointers_match == EPT_POINTERS_CHECK)
> - check_ept_pointer_match(kvm);
> + if (kvm_vmx->ept_pointers_match == EPT_POINTERS_CHECK) {
> + kvm_vmx->ept_pointers_match = EPT_POINTERS_MATCH;
> + kvm_vmx->hv_tlb_eptp = INVALID_PAGE;
> +
> + kvm_for_each_vcpu(i, vcpu, kvm) {
> + tmp_eptp = to_vmx(vcpu)->ept_pointer;
> + if (!VALID_PAGE(tmp_eptp))
> + continue;
> +
> + if (!VALID_PAGE(kvm_vmx->hv_tlb_eptp)) {
> + kvm_vmx->hv_tlb_eptp = tmp_eptp;
> + } else if (kvm_vmx->hv_tlb_eptp != tmp_eptp) {
> + kvm_vmx->hv_tlb_eptp = INVALID_PAGE;
> + kvm_vmx->ept_pointers_match
> + = EPT_POINTERS_MISMATCH;
> + break;
> + }
> + }
> + }
>
> if (kvm_vmx->ept_pointers_match != EPT_POINTERS_MATCH) {
> kvm_for_each_vcpu(i, vcpu, kvm) {

Reviewed-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>

--
Vitaly