linux-kernel - [PATCH 4/7] KVM: SVM: Return -EINVAL instead of -EBUSY on attempt to re-init SEV/SEV-ES

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Date: Mon, 18 Mar 2024 18:09:59 -0400
From: Paolo Bonzini <pbonzini@...hat.com>
To: linux-kernel@...r.kernel.org,
	kvm@...r.kernel.org
Cc: seanjc@...gle.com,
	Tom Lendacky <thomas.lendacky@....com>
Subject: [PATCH 4/7] KVM: SVM: Return -EINVAL instead of -EBUSY on attempt to re-init SEV/SEV-ES

From: Sean Christopherson <seanjc@...gle.com>

Return -EINVAL instead of -EBUSY if userspace attempts KVM_SEV{,ES}_INIT
on a VM that already has SEV active.  Returning -EBUSY is nonsencial as
it's impossible to deactivate SEV without destroying the VM, i.e. the VM
isn't "busy" in any sane sense of the word, and the odds of any userspace
wanting exactly -EBUSY on a userspace bug are minuscule.

Reviewed-by: Tom Lendacky <thomas.lendacky@....com>
Link: https://lore.kernel.org/r/20240131235609.4161407-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/svm/sev.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 5f8312edee36..f06f9e51ad9d 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -259,9 +259,8 @@ static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp)
 	if (kvm->created_vcpus)
 		return -EINVAL;
 
-	ret = -EBUSY;
 	if (unlikely(sev->active))
-		return ret;
+		return -EINVAL;
 
 	sev->active = true;
 	sev->es_active = argp->id == KVM_SEV_ES_INIT;
-- 
2.43.0