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=-5.3 required=3.0 tests=BAYES_00, 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 33DC2C4363A for ; Mon, 5 Oct 2020 20:45:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E72C720853 for ; Mon, 5 Oct 2020 20:45:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729327AbgJEUpr (ORCPT ); Mon, 5 Oct 2020 16:45:47 -0400 Received: from mga04.intel.com ([192.55.52.120]:23280 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726935AbgJEUpr (ORCPT ); Mon, 5 Oct 2020 16:45:47 -0400 IronPort-SDR: XRbupo9fQrjM7kTVjr+7iP7BFHLlwUf600Y5Ruor3O7UQc3wMmGwdGdwiaD2SNOnTku1B7WCTv bL/aKFqX8/ZQ== X-IronPort-AV: E=McAfee;i="6000,8403,9765"; a="161418525" X-IronPort-AV: E=Sophos;i="5.77,340,1596524400"; d="scan'208";a="161418525" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga104.fm.intel.com with ESMTP; 05 Oct 2020 13:17:34 -0700 IronPort-SDR: bWUdjiCtQL4FeLoEONcPOHpiol6g0UkplB0CinvIRbVF/ddxZYwUKNf8J6Yg1e32pqE2gRMdPr PzMdHdte1hIA== X-IronPort-AV: E=Sophos;i="5.77,340,1596524400"; d="scan'208";a="460048735" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.160]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Oct 2020 12:54:13 -0700 Date: Mon, 5 Oct 2020 12:54:11 -0700 From: Sean Christopherson To: Andy Lutomirski Cc: Gabriel Krisman Bertazi , Paolo Bonzini , Thomas Gleixner , Christoph Hellwig , "H. Peter Anvin" , Borislav Petkov , Robert Richter , Peter Zijlstra , Ingo Molnar , X86 ML , LKML , Dave Hansen , kernel@collabora.com Subject: Re: [PATCH v2 7/9] x86: Use current USER_CS to setup correct context on vmx entry Message-ID: <20201005195411.GB15803@linux.intel.com> References: <20201001205819.27879-1-krisman@collabora.com> <20201001205819.27879-8-krisman@collabora.com> <20201002224005.GF24460@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Oct 03, 2020 at 04:04:22PM -0700, Andy Lutomirski wrote: > On Fri, Oct 2, 2020 at 5:15 PM Andy Lutomirski wrote: > > But it's also more subtly wrong -- this corrupts all the segment attributes > > in the case where a segment points to the GDT and the GDT attributes are > > non-default. Part of me wants to ask if it's even possible to get into such a scenario, but a much larger part of me doesn't want to think about segmentation any more :-) > > I would also be okay with making the KVM code match the context switch > > code, but this may be distinctly nontrivial. Ya. > If you're okay waiting for a couple days, I'll just do this. I have > it 2/3-done already, except I'm running into the utter catastrophe > that is 32-bit stackprotector, so I'm going to fix that first. (Or > delete it if I get toosick of it.) By all means. I dragged my feet for several months, I can certainly do nothing for a few more days.