linux-kernel - [PATCH v4 4/4] KVM: SVM: Return -EINVAL instead of -EBUSY on attempt to re-init SEV/SEV-ES

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Message-ID: <20240131235609.4161407-5-seanjc@google.com>
Date: Wed, 31 Jan 2024 15:56:09 -0800
From: Sean Christopherson <seanjc@...gle.com>
To: Sean Christopherson <seanjc@...gle.com>, Paolo Bonzini <pbonzini@...hat.com>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	Ashish Kalra <ashish.kalra@....com>, Tom Lendacky <thomas.lendacky@....com>
Subject: [PATCH v4 4/4] KVM: SVM: Return -EINVAL instead of -EBUSY on attempt
 to re-init SEV/SEV-ES

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.

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 38e40fbc7ea0..cb19b57e1031 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;
-- 
2.43.0.429.g432eaa2c6b-goog