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=-7.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 8FCF7C48BDF for ; Thu, 10 Jun 2021 13:23:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 75D69613F5 for ; Thu, 10 Jun 2021 13:23:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230381AbhFJNZ3 (ORCPT ); Thu, 10 Jun 2021 09:25:29 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:39229 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230322AbhFJNZ2 (ORCPT ); Thu, 10 Jun 2021 09:25:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1623331412; 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=88ww2xQY0H+0+XkZE9y7YZG1xhuZT7Zms2aalO6pzRo=; b=dN/SKWoOMtsPnwSsqg61lvd5Pjqpc2bKrciIu9DNRD7PxgmdSnea/NJht8BX7ikzN70d3L V4gTBD6YnptLwiLitinPROxd+Bcwdc31IuNvrwhfZMx2aj3RKMdRJKocgidqs8FQJaVo95 oXZnxq+cFNV5vZj0Oq3baslnSUSg3Us= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-164-An8N__SWOheIqPQNPs594g-1; Thu, 10 Jun 2021 09:23:30 -0400 X-MC-Unique: An8N__SWOheIqPQNPs594g-1 Received: by mail-wm1-f69.google.com with SMTP id m31-20020a05600c3b1fb02901bd331ed39fso456070wms.0 for ; Thu, 10 Jun 2021 06:23:30 -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=88ww2xQY0H+0+XkZE9y7YZG1xhuZT7Zms2aalO6pzRo=; b=ieD5ial7HBpeP7/Mi7TnHj2ToDM1mn//Jb9T9gMXRhxLCm63hNZxoT6F8zqK4n/rev bdrdbvVWacOSNXP+5t7veM6Zg67wGz/RW4MiZo2Ja9jBo3xbFdlTuxQiEpD9lbMbi7tj ZDqqSs51lvypVBfVLhIazOrB5DugghLX+xdIL+SF2cxSzp46RPIt29lJWoX3k0/oHhXc crK99piS54p1Eq8G6N9MjqUHMfHuYkPgyx3Wii79+o3LFgFlzDdKfJKMBh0rG5pez5rC CJ6ADE4WGBMI1O6Y5THF/hJ+BsFJtNPXriIZu0wvnMU4nP5X0kiE4GlZLR67ZL8mKi4q +hsA== X-Gm-Message-State: AOAM53169PahKv0GDoCRpT8DpetMiGIdqMDKmLZVdmUTAF8kCetQ60O9 IU+dGLoPcj3m89gRLcnAEaHanQtsI+hE5GHORH09iXYppjenuBmV4xbHimLD1xI4rLrFjek45O2 PQ8iY85SKswOkX0ltJ8n/J44V X-Received: by 2002:a05:600c:350a:: with SMTP id h10mr5114454wmq.164.1623331409582; Thu, 10 Jun 2021 06:23:29 -0700 (PDT) X-Google-Smtp-Source: ABdhPJw79lNKYMmKsJc+6kNvOS13CVwEmBkp0QyLoPEBLj7gbej3FcuzIUPP6197YkoOsIew2kREgw== X-Received: by 2002:a05:600c:350a:: with SMTP id h10mr5114437wmq.164.1623331409407; Thu, 10 Jun 2021 06:23:29 -0700 (PDT) Received: from ?IPv6:2001:b07:6468:f312:63a7:c72e:ea0e:6045? ([2001:b07:6468:f312:63a7:c72e:ea0e:6045]) by smtp.gmail.com with ESMTPSA id o3sm4347353wrc.0.2021.06.10.06.23.27 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 10 Jun 2021 06:23:28 -0700 (PDT) Subject: Re: [PATCH 2/9] KVM: x86: Emulate triple fault shutdown if RSM emulation fails To: Sean Christopherson Cc: Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+fb0b6a7e8713aeb0319c@syzkaller.appspotmail.com References: <20210609185619.992058-1-seanjc@google.com> <20210609185619.992058-3-seanjc@google.com> From: Paolo Bonzini Message-ID: <520185e2-fe95-6ab6-163c-a46bfaa1f5d5@redhat.com> Date: Thu, 10 Jun 2021 15:23:27 +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: <20210609185619.992058-3-seanjc@google.com> 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 09/06/21 20:56, Sean Christopherson wrote: > For recent Intel CPUs, restoring NMI blocking is technically wrong, but > so is restoring NMI blocking in the first place, and Intel's RSM > "architecture" is such a mess that just about anything is allowed and can > be justified as micro-architectural behavior. The Intel manual is an absolute mess with respect to NMI blocking, and for once AMD followed suit. Some versions of the AMD BIOS and Kernel Developer Manual provide the offset of the "NMI masked" flag in the SMM state save area, but unfortunately that was discovered too late. Paolo