Commit 9ebe530b authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: SVM: Move RESET emulation to svm_vcpu_reset() 



Move RESET emulation for SVM vCPUs to svm_vcpu_reset(), and drop an extra
init_vmcb() from svm_create_vcpu() in the process.  Hopefully KVM will
someday expose a dedicated RESET ioctl(), and in the meantime separating
"create" from "RESET" is a nice cleanup.

Keep the call to svm_switch_vmcb() so that misuse of svm->vmcb at worst
breaks the guest, e.g. premature accesses doesn't cause a NULL pointer
dereference.

Cc: Reiji Watanabe <reijiw@google.com>
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210921000303.400537-10-seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 06692e4b

arch/x86/kvm/svm/sev.c

+3 −3
Original line number Diff line number Diff line
@@ -2631,11 +2631,11 @@ void sev_es_init_vmcb(struct vcpu_svm *svm) 
	set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 1, 1);

}



void sev_es_create_vcpu(struct vcpu_svm *svm)

void sev_es_vcpu_reset(struct vcpu_svm *svm)

{

	/*

	 * Set the GHCB MSR value as per the GHCB specification when creating

	 * a vCPU for an SEV-ES guest.

	 * Set the GHCB MSR value as per the GHCB specification when emulating

	 * vCPU RESET for an SEV-ES guest.

	 */

	set_ghcb_msr(svm, GHCB_MSR_SEV_INFO(GHCB_VERSION_MAX,

					    GHCB_VERSION_MIN,

arch/x86/kvm/svm/svm.c

+17 −12
Original line number Diff line number Diff line
@@ -1303,6 +1303,19 @@ static void init_vmcb(struct kvm_vcpu *vcpu) 


}



static void __svm_vcpu_reset(struct kvm_vcpu *vcpu)

{

	struct vcpu_svm *svm = to_svm(vcpu);



	svm_vcpu_init_msrpm(vcpu, svm->msrpm);



	svm_init_osvw(vcpu);

	vcpu->arch.microcode_version = 0x01000065;



	if (sev_es_guest(vcpu->kvm))

		sev_es_vcpu_reset(svm);

}



static void svm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)

{

	struct vcpu_svm *svm = to_svm(vcpu);
@@ -1311,6 +1324,9 @@ static void svm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) 
	svm->virt_spec_ctrl = 0;



	init_vmcb(vcpu);



	if (!init_event)

		__svm_vcpu_reset(vcpu);

}



void svm_switch_vmcb(struct vcpu_svm *svm, struct kvm_vmcb_info *target_vmcb)
@@ -1370,24 +1386,13 @@ static int svm_create_vcpu(struct kvm_vcpu *vcpu) 


	svm->vmcb01.ptr = page_address(vmcb01_page);

	svm->vmcb01.pa = __sme_set(page_to_pfn(vmcb01_page) << PAGE_SHIFT);

	svm_switch_vmcb(svm, &svm->vmcb01);



	if (vmsa_page)

		svm->vmsa = page_address(vmsa_page);



	svm->guest_state_loaded = false;



	svm_switch_vmcb(svm, &svm->vmcb01);

	init_vmcb(vcpu);



	svm_vcpu_init_msrpm(vcpu, svm->msrpm);



	svm_init_osvw(vcpu);

	vcpu->arch.microcode_version = 0x01000065;



	if (sev_es_guest(vcpu->kvm))

		/* Perform SEV-ES specific VMCB creation updates */

		sev_es_create_vcpu(svm);



	return 0;



error_free_vmsa_page:

arch/x86/kvm/svm/svm.h

+1 −1
Original line number Diff line number Diff line
@@ -562,7 +562,7 @@ void sev_free_vcpu(struct kvm_vcpu *vcpu); 
int sev_handle_vmgexit(struct kvm_vcpu *vcpu);

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_create_vcpu(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_unmap_ghcb(struct vcpu_svm *svm);