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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 71EC1C7618F for ; Mon, 15 Jul 2019 13:05:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3C31E2080A for ; Mon, 15 Jul 2019 13:05:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730142AbfGONFh (ORCPT ); Mon, 15 Jul 2019 09:05:37 -0400 Received: from mail-wm1-f66.google.com ([209.85.128.66]:54440 "EHLO mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730048AbfGONFh (ORCPT ); Mon, 15 Jul 2019 09:05:37 -0400 Received: by mail-wm1-f66.google.com with SMTP id p74so15077570wme.4 for ; Mon, 15 Jul 2019 06:05:35 -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:openpgp:message-id :date:user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=4IkpEIRyxTphY4AHIBJmmlbcwMrkgGFJBoEkjGVA36A=; b=fVKde8VM1VvjZdKfU7XsdMwLWwuYldzFHzcnNGr96TKJD5wbaHsztJ2VNZvY4TBy0s uxR0ddzn1b8Kp4Xcwpv02KPzb2aoDZSwNBz6oAOwhl/ZOu3eubNqjULk/zRClUm+h2gg 1IA77DRzF6EdIGNFrA3aCUPFEtHbuQM35aikukh7Gat+WlosActLY7lAJFi8CGhgDIhA CwMZUtrD3QJtJ/hK6OvSpkEeN7Glfq9IruLx/BRfG3JfkcKm+jhRvTZCgkcA8OZQ87xU A1SvEia6L6NLjvkkzUZGw2H+9KtilQgdeFSEHZqWnYwna2KhlgOFj6WySX9oEZsJlwzf nRjw== X-Gm-Message-State: APjAAAWwIaG4sc8P6ClXFLBykJgTq8C/xHABWXrmefKrLkD5oVtg9oHc WJr6fJDalo9vIIPf1zSA2W9XOw== X-Google-Smtp-Source: APXvYqxgGsTksSywgyrRHsQXv3t+Rd7r4vdMOlKwU+lYO7CkTQYdi3hA7dF5XFSeqjisRCWDXeLYkQ== X-Received: by 2002:a05:600c:214e:: with SMTP id v14mr25351143wml.96.1563195935198; Mon, 15 Jul 2019 06:05:35 -0700 (PDT) Received: from [192.168.178.40] ([151.20.129.151]) by smtp.gmail.com with ESMTPSA id 91sm34867134wrp.3.2019.07.15.06.05.34 (version=TLS1_3 cipher=AEAD-AES128-GCM-SHA256 bits=128/128); Mon, 15 Jul 2019 06:05:34 -0700 (PDT) Subject: Re: [PATCH 04/22] x86/kvm: Don't call kvm_spurious_fault() from .fixup To: Josh Poimboeuf Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Peter Zijlstra , Thomas Gleixner , Nick Desaulniers , Arnd Bergmann , Jann Horn , Randy Dunlap , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= References: <1f37a9e42732c224bc5299dbc827b4101c9deb22.1563150885.git.jpoimboe@redhat.com> <07b8513a-d8f7-f8cf-daf6-83a80ade987a@redhat.com> <20190715124025.prcetv24oyjnuvip@treble> From: Paolo Bonzini Openpgp: preference=signencrypt Message-ID: <29d30d81-bcbe-5261-b34d-12bd62df9116@redhat.com> Date: Mon, 15 Jul 2019 15:05:33 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20190715124025.prcetv24oyjnuvip@treble> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 15/07/19 14:40, Josh Poimboeuf wrote: >>> * Hardware virtualization extension instructions may fault if a >>> * reboot turns off virtualization while processes are running. >>> - * Trap the fault and ignore the instruction if that happens. >>> + * If that happens, trap the fault and panic (unless we're rebooting). >> Not sure the comment is better than before, but apar from that > The previous comment didn't seem to match the code, since we only ignore > the instruction if we're rebooting. > "If that happens" refers to "a reboot turns off virtualization while processes are running". Perhaps * Usually after catching the fault we just panic; during reboot * instead the instruction is ignored. Paolo