From patchwork Tue Mar 4 06:06:42 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 13999956 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1BF121F5845 for ; Tue, 4 Mar 2025 06:07:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741068427; cv=none; b=fsJSygCs5oLylwK7QdXHXQKv/6Rda+MODRNLXMhzKDNtFBv88q4FMKQRGX6k4AxSHzAxmZhY5ZHTqpDMHypHFwwB3pqSfDkMGV6SM8u0mewd0sO8U0vFA+pP+k+MUEeyB/+6omygE0Swk4m9Q9LxvDQ947Ke4hDLEpuLsYRy++g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741068427; c=relaxed/simple; bh=WsLGljyHCX0zroN9NjHxnwSRav5wouWwgj/kVngfrBU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=hFvnyMvbQPs2deJ/Iy4oS7gQIwJzoVCv/wAMIBMe2dJ1svUvOAELNniUvyVKfAw2sM0OpLwTyCL/Xf5L8RkuepPykT92QKY2qVHT3JBvEc0rk2RKZdF/Lh6w0+1snVNGSJB5d86gp/4XsZWa2bV6pzowiNfScCR2fZXQU2l+XO8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=TN81XJiN; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="TN81XJiN" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1741068425; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=GdEIWZIH2eKGHtQySdvQ9TzxOHVfZXOqEG078/YncxI=; b=TN81XJiNupxhUx9z4FxsvBmKKGyIL3wtXY+es5tHJC3S+n7oZ1zkJ29uISrlBAqQ9gaMXq //HSS2OoBntqiKro/CG9O59JWHyX8gRzit6ycFAwr6XylVmho0iM7RGQ2sm4aH8THMz5D7 B4+J+q2KxaKIcUrVwE9sUq6MJ+Q6W4E= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-61-zm5kK5PXPheefPrXRTyvEQ-1; Tue, 04 Mar 2025 01:06:51 -0500 X-MC-Unique: zm5kK5PXPheefPrXRTyvEQ-1 X-Mimecast-MFC-AGG-ID: zm5kK5PXPheefPrXRTyvEQ_1741068410 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 52D491944D45; Tue, 4 Mar 2025 06:06:50 +0000 (UTC) Received: from virtlab1023.lab.eng.rdu2.redhat.com (virtlab1023.lab.eng.rdu2.redhat.com [10.8.1.187]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 6860519560A3; Tue, 4 Mar 2025 06:06:49 +0000 (UTC) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: xiaoyao.li@intel.com, seanjc@google.com, yan.y.zhao@intel.com Subject: [PATCH v3 1/6] KVM: x86: do not allow re-enabling quirks Date: Tue, 4 Mar 2025 01:06:42 -0500 Message-ID: <20250304060647.2903469-2-pbonzini@redhat.com> In-Reply-To: <20250304060647.2903469-1-pbonzini@redhat.com> References: <20250304060647.2903469-1-pbonzini@redhat.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Allowing arbitrary re-enabling of quirks puts a limit on what the quirks themselves can do, since you cannot assume that the quirk prevents a particular state. More important, it also prevents KVM from disabling a quirk at VM creation time, because userspace can always go back and re-enable that. Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 856ceeb4fb35..35d03fcdb8e9 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6525,7 +6525,7 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm, break; fallthrough; case KVM_CAP_DISABLE_QUIRKS: - kvm->arch.disabled_quirks = cap->args[0]; + kvm->arch.disabled_quirks |= cap->args[0]; r = 0; break; case KVM_CAP_SPLIT_IRQCHIP: {