From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 640FFC49361 for ; Fri, 18 Jun 2021 10:27:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4574E613F3 for ; Fri, 18 Jun 2021 10:27:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233605AbhFRK3p (ORCPT ); Fri, 18 Jun 2021 06:29:45 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:31149 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229768AbhFRK3l (ORCPT ); Fri, 18 Jun 2021 06:29:41 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1624012052; 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=6Z2CJ9V34y2pAE384/ANEr0yGKWrtOTaGvsqCpVRS+U=; b=CVBuJ4scA8FL49OKv6xID43XZuJf1ezm4VEWdMRqBng1vmmHuR+XaRzKMNWH1zL75Pvj7F bxuvkA/M7bNqCdXo2DpVcyp4ICkhdSdNpc2ljOZCZck8eUmaNwkYHCLCEzElXfPcqHgIFM zJW7KwPxmKYzi7p75aKz354QHE8YEAQ= Received: from mail-ed1-f72.google.com (mail-ed1-f72.google.com [209.85.208.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-159-neHOHbioNcmu42HQJ3SNLA-1; Fri, 18 Jun 2021 06:27:31 -0400 X-MC-Unique: neHOHbioNcmu42HQJ3SNLA-1 Received: by mail-ed1-f72.google.com with SMTP id a16-20020aa7cf100000b0290391819a774aso1723622edy.8 for ; Fri, 18 Jun 2021 03:27:30 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=6Z2CJ9V34y2pAE384/ANEr0yGKWrtOTaGvsqCpVRS+U=; b=ml3Z7DhJ7Vm+0SeNIRftYI2h7b+oJrJCrZFQW1FqgtgicJ/h9SrHbGfl58pCxILMnO gYlq+qvexaKakL0lG/4gqcv5cFrL2drVkTIRPa3TTr4t9tMXUUY3uUlcLHxhEaNaOVxU QUhp9X9LS3e5zz6bIKEw2OHtFexUOsM+mB/WZAGAZZEEGBBD2BLoiKD3DsBoKaXndJWQ QZHEgEWjGMQ8zdS7XLJ8kobWTxfX8frUerPEqQWKLNq4Dgilh+Wd+doEynz7aTaNjim3 vO6TNOg1Hbb03u/B8vPvGoK/BTi4fVvTHZ3QCHEDvhvIiI/3UeQAQIrfeQ0nipQETOAf uqRQ== X-Gm-Message-State: AOAM5326ezK0RiiV9F5qmfo//Oc3Gcs8mOSxRQUKhltVTU8kA0M9LaeC TbtQqqLrGrjg1GUAXLZaaTNYNO/PmECF4ui/gxgGOm+bc3TF/giDXupd9O6ZSFxSD9vVxAwvwyW 5AzoXark5J5ECFnIZYUiGwkkPc7o8hHw9kOWhFnI6/PyqU/QAl44mUdql/nx4YbrZf30Md1Tq2T XD X-Received: by 2002:a17:906:3057:: with SMTP id d23mr10217667ejd.131.1624012049534; Fri, 18 Jun 2021 03:27:29 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyXkfkJJzO9ow7Rx03C2rZ0ep5F363V1TXI14icaVSd94bulhKHWZRzimP1DHsWrjdYztsWog== X-Received: by 2002:a17:906:3057:: with SMTP id d23mr10217649ejd.131.1624012049358; Fri, 18 Jun 2021 03:27:29 -0700 (PDT) Received: from ?IPv6:2001:b07:6468:f312:c8dd:75d4:99ab:290a? ([2001:b07:6468:f312:c8dd:75d4:99ab:290a]) by smtp.gmail.com with ESMTPSA id n13sm848630ejk.97.2021.06.18.03.27.28 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 18 Jun 2021 03:27:28 -0700 (PDT) Subject: Re: [PATCH 3/4] KVM: x86: WARN and reject loading KVM if NX is supported but not enabled To: Jim Mattson , Sean Christopherson Cc: Vitaly Kuznetsov , Wanpeng Li , Joerg Roedel , kvm list , LKML References: <20210615164535.2146172-1-seanjc@google.com> <20210615164535.2146172-4-seanjc@google.com> From: Paolo Bonzini Message-ID: <6ea2385a-9abe-82b8-6c57-8dc3aac824b2@redhat.com> Date: Fri, 18 Jun 2021 12:27:27 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 16/06/21 00:39, Jim Mattson wrote: >> >> rdmsrl_safe(MSR_EFER, &host_efer); >> + if (WARN_ON_ONCE(boot_cpu_has(X86_FEATURE_NX) && >> + !(host_efer & EFER_NX))) >> + return -EIO; > Input/output error? Is that really the most appropriate error here? > Why not, say, -ENOTSUP? > > I'm sure there's some arcane convention here that I'm not privy to.:-) > > Reviewed-by: Jim Mattson > EIO often means "how the heck did we get here?" or "look in dmesg to get more info", both of which I think are appropriate after a WARN. Paolo