From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754677AbcEDWPl (ORCPT ); Wed, 4 May 2016 18:15:41 -0400 Received: from mga01.intel.com ([192.55.52.88]:42782 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754377AbcEDWPk (ORCPT ); Wed, 4 May 2016 18:15:40 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,579,1455004800"; d="scan'208";a="799059066" Subject: Re: [PATCH v4 10/10] x86/xsaves: Re-enable XSAVES To: Yu-cheng Yu References: <5723C4CF.3050209@linux.intel.com> <20160429231252.GA15765@test-lenovo> <5723FF0C.2020905@linux.intel.com> <20160502161135.GA21625@test-lenovo> Cc: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, Andy Lutomirski , Borislav Petkov , Sai Praneeth Prakhya , "Ravi V. Shankar" , Fenghua Yu From: Dave Hansen Message-ID: <572A748A.1000401@linux.intel.com> Date: Wed, 4 May 2016 15:15:38 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <20160502161135.GA21625@test-lenovo> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/02/2016 09:11 AM, Yu-cheng Yu wrote: > On Fri, Apr 29, 2016 at 05:40:44PM -0700, Dave Hansen wrote: >> That's better than what we had before, but it relies entirely on testing >> coverage and runtime checks. >> >> Is it too much to ask that you also take a look and audit all the places >> the XSAVE buffer is accessed in the kernel and ensure that they either >> have code to handle standard vs. compacted/supervisor or don't care for >> some reason? >> >> I did such an audit once upon a time, but I think it would be a good >> exercise to repeat both by a second set of eyes and because some time >> has passed. > > I think there are 12 files that can be directly impacted by XSAVES. > > arch/x86/include/asm/fpu/internal.h > arch/x86/include/asm/fpu/types.h > arch/x86/include/asm/fpu/xstate.h > arch/x86/include/uapi/asm/sigcontext.h > arch/x86/kernel/traps.c > arch/x86/kernel/fpu/core.c > arch/x86/kernel/fpu/init.c > arch/x86/kernel/fpu/regset.c > arch/x86/kernel/fpu/signal.c > arch/x86/kernel/fpu/xstate.c > arch/x86/kvm/x86.c > arch/x86/mm/mpx.c > > They have been reviewed from the perspective of the compacted format. > Please let me know anything else. Can you double-check that nothing has changed in mainline (or tip for that matter) since you first did these checks?