Commit bc3d7c55 authored by Peter Gonda's avatar Peter Gonda Committed by Sean Christopherson
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KVM: SVM: Update SEV-ES shutdown intercepts with more metadata 



Currently if an SEV-ES VM shuts down userspace sees KVM_RUN struct with
only errno=EINVAL. This is a very limited amount of information to debug
the situation. Instead return KVM_EXIT_SHUTDOWN to alert userspace the VM
is shutting down and is not usable any further.

Signed-off-by: default avatarPeter Gonda <pgonda@google.com>
Suggested-by: default avatarSean Christopherson <seanjc@google.com>
Suggested-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20230907162449.1739785-1-pgonda@google.com


[sean: tweak changelog]
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 5804c19b

arch/x86/kvm/svm/svm.c

+7 −8
Original line number Diff line number Diff line
@@ -2203,12 +2203,6 @@ static int shutdown_interception(struct kvm_vcpu *vcpu) 
	struct kvm_run *kvm_run = vcpu->run;

	struct vcpu_svm *svm = to_svm(vcpu);



	/*

	 * The VM save area has already been encrypted so it

	 * cannot be reinitialized - just terminate.

	 */

	if (sev_es_guest(vcpu->kvm))

		return -EINVAL;



	/*

	 * VMCB is undefined after a SHUTDOWN intercept.  INIT the vCPU to put
@@ -2217,9 +2211,14 @@ static int shutdown_interception(struct kvm_vcpu *vcpu) 
	 * userspace.  At a platform view, INIT is acceptable behavior as

	 * there exist bare metal platforms that automatically INIT the CPU

	 * in response to shutdown.

	 *

	 * The VM save area for SEV-ES guests has already been encrypted so it

	 * cannot be reinitialized, i.e. synthesizing INIT is futile.

	 */

	if (!sev_es_guest(vcpu->kvm)) {

		clear_page(svm->vmcb);

		kvm_vcpu_reset(vcpu, true);

	}



	kvm_run->exit_reason = KVM_EXIT_SHUTDOWN;

	return 0;