From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751651AbcBYU5b (ORCPT ); Thu, 25 Feb 2016 15:57:31 -0500 Received: from mga04.intel.com ([192.55.52.120]:6964 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751179AbcBYU53 (ORCPT ); Thu, 25 Feb 2016 15:57:29 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,498,1449561600"; d="scan'208";a="921258574" Subject: Re: [PATCH v2 0/9] x86/xsaves: Fix XSAVES known issues To: Yu-cheng Yu , x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org References: Cc: Andy Lutomirski , Borislav Petkov , Sai Praneeth Prakhya , "Ravi V. Shankar" , Fenghua Yu From: Dave Hansen Message-ID: <56CF6AB8.1050803@linux.intel.com> Date: Thu, 25 Feb 2016 12:57:28 -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: 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 02/25/2016 12:26 PM, Yu-cheng Yu wrote: > Patch 9 re-enables XSAVES. Could we also add one more thing to this: A big, fat warning that supervisor states are not supported? We might get that from an eventual use of xfeature_uncompacted_offset(), but we need something that's very clear. I just don't want somebody coming along and shoving a supervisor state in to XCR0 and expecting it to work just because we have XSAVES support itself. That might happen in-tree or out-of-tree as things get prototyped.