From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758665Ab3LFRzb (ORCPT ); Fri, 6 Dec 2013 12:55:31 -0500 Received: from terminus.zytor.com ([198.137.202.10]:59201 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754412Ab3LFRz2 (ORCPT ); Fri, 6 Dec 2013 12:55:28 -0500 Message-ID: <52A20F80.9000601@zytor.com> Date: Fri, 06 Dec 2013 09:55:12 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0 MIME-Version: 1.0 To: Paolo Bonzini , Qiaowei Ren CC: Thomas Gleixner , Ingo Molnar , x86@kernel.org, linux-kernel@vger.kernel.org, qemu-devel@nongnu.org, kvm@vger.kernel.org, Xudong Hao , Liu Jinsong Subject: Re: [PATCH v2 3/3] X86, mpx: Intel MPX xstate feature definition References: <1386375658-2191-1-git-send-email-qiaowei.ren@intel.com> <1386375658-2191-3-git-send-email-qiaowei.ren@intel.com> <52A20AD6.8080706@redhat.com> In-Reply-To: <52A20AD6.8080706@redhat.com> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/06/2013 09:35 AM, Paolo Bonzini wrote: > > Sorry for the back-and-forth, but I think this and the removal of > XSTATE_FLEXIBLE (perhaps XSTATE_LAZY?) makes your v2 worse than v1. > > Since Peter already said the same, please undo these changes. > > Also, how is XSTATE_EAGER used? Should MPX be disabled when xsaveopt is > disabled on the kernel command line? (Liu, how would this affect the > KVM patches, too?) > There are two options: we could disable MPX etc. or we could force eager saving (using xsave) even if xsaveopt is disabled. It is a hard call to make, but I guess I'm leaning towards the latter; we could add an "lazyxsave" option to explicitly disable all eager features if there is use for that. -hpa