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=-13.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 DFFFCC433E0 for ; Wed, 24 Feb 2021 00:31:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9092D64EC8 for ; Wed, 24 Feb 2021 00:31:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233845AbhBXA0h (ORCPT ); Tue, 23 Feb 2021 19:26:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36772 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234248AbhBWXuS (ORCPT ); Tue, 23 Feb 2021 18:50:18 -0500 Received: from mail-pg1-x535.google.com (mail-pg1-x535.google.com [IPv6:2607:f8b0:4864:20::535]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CDDA4C06178A for ; Tue, 23 Feb 2021 15:42:06 -0800 (PST) Received: by mail-pg1-x535.google.com with SMTP id e6so234747pgk.5 for ; Tue, 23 Feb 2021 15:42:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=XmdEFwlRSgTwWjhTIOCD45ph+gJBk6ITkuI62uYBDIg=; b=eXy+FB07yVuJ6/cjvt5/xXTNB5HkilzciwQ3E62QYNk88ggJ5p4xodew9wvHKDwQW2 MUjiv3z8KgJ1243MREGKwB37pRozEyiSkhGqmEt+F02HjduI5yhia6e0KDoI3Ykfed90 K791jSCktesKHq8oeNRISv5v8RnPu2YH7lrhw6WukXGiuNXQ61LwWb/BgZ3+44mWeXUt MprZjNzRJ09BhYQBoRiFfLnJhQRuitckB7jXR8bpTpEe2vCzKi8MvNXDfDiH+FzzPoi6 IdZfv7qhWY4zoDEQ/rlC6p6qQQALcyFsiAc01hpUQvmTn4FyP6L2f5BWMUtaIWQH7YIi fEjQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=XmdEFwlRSgTwWjhTIOCD45ph+gJBk6ITkuI62uYBDIg=; b=oEnKCbD5ibnuFnEJyI1jecBMzOZMR/AUMX9SDQJedlhyX8bLjGOJAbIkOHZRy0B6ZU 471jC1Vy7hNQ9qui3JlsV00mJQcRGo/RsmULYwxayzUAugGYT9KIlvwD74VekcKJy3aR 0ZsaN3WOAi0b6XrtfkWhYodK+csU6X0kbslu0vGRxrfGtdLG6LFIQwSfhVIYF/oqyLQF r4N1a7tMhQZ3dC8hSuZRNSVbnIb7I3QJWlPDbrDbD7sbyqq8rqUPlUojI9bZ5Itwq1Bf w5tCSlWeGh/iUkXg1VbpLOchK3Jrq3DmfcfjSwBuMfOOuxGsEtbW4notN8Z2BPUh/G1+ e+Sg== X-Gm-Message-State: AOAM533MvBTPN84GTObUy1H6K8y0sOIz7tdnRDDTmADOOEiaE+BYFe8/ DOLdTbOABWd/5uwxdXG2Cefhpw== X-Google-Smtp-Source: ABdhPJw0H/0JO4IDoJrNMO3b+L5jJU62/Ziwu57iowle9OzZNgacqILcHibge23EoOYkCUkn0n2HVQ== X-Received: by 2002:a63:da4a:: with SMTP id l10mr26339797pgj.222.1614123726083; Tue, 23 Feb 2021 15:42:06 -0800 (PST) Received: from google.com ([2620:15c:f:10:385f:4012:d20f:26b5]) by smtp.gmail.com with ESMTPSA id c22sm297716pfc.12.2021.02.23.15.42.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Feb 2021 15:42:05 -0800 (PST) Date: Tue, 23 Feb 2021 15:41:58 -0800 From: Sean Christopherson To: Jim Mattson Cc: David Edmondson , LKML , "H. Peter Anvin" , Joerg Roedel , the arch/x86 maintainers , Thomas Gleixner , kvm list , Paolo Bonzini , Wanpeng Li , Ingo Molnar , Borislav Petkov , Vitaly Kuznetsov Subject: Re: [PATCH v2 1/3] KVM: x86: dump_vmcs should not assume GUEST_IA32_EFER is valid Message-ID: References: <20210219144632.2288189-1-david.edmondson@oracle.com> <20210219144632.2288189-2-david.edmondson@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 23, 2021, Jim Mattson wrote: > On Tue, Feb 23, 2021 at 2:51 PM Sean Christopherson wrote: > > > > On Fri, Feb 19, 2021, David Edmondson wrote: > > > If the VM entry/exit controls for loading/saving MSR_EFER are either > > > not available (an older processor or explicitly disabled) or not > > > used (host and guest values are the same), reading GUEST_IA32_EFER > > > from the VMCS returns an inaccurate value. > > > > > > Because of this, in dump_vmcs() don't use GUEST_IA32_EFER to decide > > > whether to print the PDPTRs - do so if the EPT is in use and CR4.PAE > > > is set. > > > > This isn't necessarily correct either. In a way, it's less correct as PDPTRs > > are more likely to be printed when they shouldn't, assuming most guests are > > 64-bit guests. It's annoying to calculate the effective guest EFER, but so > > awful that it's worth risking confusion over PDTPRs. > > I still prefer a dump_vmcs that always dumps every VMCS field. I'm a-ok with that approach.