Commit 068f7ea6 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

KVM: SVM: improve split between svm_prepare_guest_switch and sev_es_prepare_guest_switch 



KVM performs the VMSAVE to the host save area for both regular and SEV-ES
guests, so hoist it up to svm_prepare_guest_switch.  And because
sev_es_prepare_guest_switch does not really need to know the details
of struct svm_cpu_data *, just pass it the pointer to the host save area
inside the HSAVE page.

Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 98242dca

arch/x86/kvm/svm/sev.c

+4 −8
Original line number Diff line number Diff line
@@ -2907,20 +2907,16 @@ void sev_es_vcpu_reset(struct vcpu_svm *svm) 
					    sev_enc_bit));

}



void sev_es_prepare_guest_switch(struct vcpu_svm *svm, unsigned int cpu)

void sev_es_prepare_guest_switch(struct vmcb_save_area *hostsa)

{

	struct svm_cpu_data *sd = per_cpu(svm_data, cpu);

	struct vmcb_save_area *hostsa;



	/*

	 * As an SEV-ES guest, hardware will restore the host state on VMEXIT,

	 * of which one step is to perform a VMLOAD. Since hardware does not

	 * perform a VMSAVE on VMRUN, the host savearea must be updated.

	 * of which one step is to perform a VMLOAD.  KVM performs the

	 * corresponding VMSAVE in svm_prepare_guest_switch for both

	 * traditional and SEV-ES guests.

	 */

	vmsave(__sme_page_pa(sd->save_area));



	/* XCR0 is restored on VMEXIT, save the current host value */

	hostsa = (struct vmcb_save_area *)(page_address(sd->save_area) + 0x400);

	hostsa->xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);



	/* PKRU is restored on VMEXIT, save the current host value */

arch/x86/kvm/svm/svm.c

+5 −3
Original line number Diff line number Diff line
@@ -1280,10 +1280,12 @@ static void svm_prepare_guest_switch(struct kvm_vcpu *vcpu) 
	 * Save additional host state that will be restored on VMEXIT (sev-es)

	 * or subsequent vmload of host save area.

	 */

	if (sev_es_guest(vcpu->kvm)) {

		sev_es_prepare_guest_switch(svm, vcpu->cpu);

	} else {

	vmsave(__sme_page_pa(sd->save_area));

	if (sev_es_guest(vcpu->kvm)) {

		struct vmcb_save_area *hostsa;

		hostsa = (struct vmcb_save_area *)(page_address(sd->save_area) + 0x400);



		sev_es_prepare_guest_switch(hostsa);

	}



	if (tsc_scaling) {

arch/x86/kvm/svm/svm.h

+1 −1
Original line number Diff line number Diff line
@@ -606,7 +606,7 @@ int sev_es_string_io(struct vcpu_svm *svm, int size, unsigned int port, int in); 
void sev_es_init_vmcb(struct vcpu_svm *svm);

void sev_es_vcpu_reset(struct vcpu_svm *svm);

void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector);

void sev_es_prepare_guest_switch(struct vcpu_svm *svm, unsigned int cpu);

void sev_es_prepare_guest_switch(struct vmcb_save_area *hostsa);

void sev_es_unmap_ghcb(struct vcpu_svm *svm);



/* vmenter.S */