From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756049AbcBVWTM (ORCPT ); Mon, 22 Feb 2016 17:19:12 -0500 Received: from mga03.intel.com ([134.134.136.65]:48831 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755877AbcBVWTJ (ORCPT ); Mon, 22 Feb 2016 17:19:09 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,486,1449561600"; d="scan'208";a="918772011" Subject: Re: [PATCH 08/10] x86/xsaves: Fix PTRACE frames for XSAVES To: Yu-cheng Yu References: <1456167621-3974-1-git-send-email-yu-cheng.yu@intel.com> <56CB68C2.6010003@linux.intel.com> <20160222204828.GC4140@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: <56CB8959.9090009@linux.intel.com> Date: Mon, 22 Feb 2016 14:19:05 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <20160222204828.GC4140@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 02/22/2016 12:48 PM, Yu-cheng Yu wrote: > It should have been: > > xsave->header.xfeatures = xfeatures | > (xsave->header.xfeatures & XFEATURE_MASK_SUPERVISOR); > > I'll fix it. Can we break it out to make it more clear? /* * The state that came in from userspace was user-state only. * Mask all the user states out of 'xfeatures'. */ xsave->header.xfeatures &= XFEATURE_MASK_SUPERVISOR; /* * add back in the features that came in from userspace */ xsave->header.xfeatures |= xfeatures