From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f45.google.com (mail-pa0-f45.google.com [209.85.220.45]) by kanga.kvack.org (Postfix) with ESMTP id B9EC56B0035 for ; Thu, 24 Jul 2014 00:46:32 -0400 (EDT) Received: by mail-pa0-f45.google.com with SMTP id eu11so3104992pac.18 for ; Wed, 23 Jul 2014 21:46:32 -0700 (PDT) Received: from mga09.intel.com (mga09.intel.com. [134.134.136.24]) by mx.google.com with ESMTP id ff3si4620953pbd.167.2014.07.23.21.46.31 for ; Wed, 23 Jul 2014 21:46:31 -0700 (PDT) Message-ID: <53D08FA4.4030700@intel.com> Date: Wed, 23 Jul 2014 21:46:28 -0700 From: Dave Hansen MIME-Version: 1.0 Subject: Re: [PATCH v7 03/10] x86, mpx: add macro cpu_has_mpx References: <1405921124-4230-1-git-send-email-qiaowei.ren@intel.com> <1405921124-4230-4-git-send-email-qiaowei.ren@intel.com> <53CE8EEC.2090402@intel.com> <9E0BE1322F2F2246BD820DA9FC397ADE0170079E@shsmsx102.ccr.corp.intel.com> <53CFDC79.8040804@intel.com> <9E0BE1322F2F2246BD820DA9FC397ADE01703028@shsmsx102.ccr.corp.intel.com> In-Reply-To: <9E0BE1322F2F2246BD820DA9FC397ADE01703028@shsmsx102.ccr.corp.intel.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: "Ren, Qiaowei" , "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar Cc: "x86@kernel.org" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" On 07/23/2014 05:56 PM, Ren, Qiaowei wrote: > On 2014-07-24, Hansen, Dave wrote: >> On 07/22/2014 07:35 PM, Ren, Qiaowei wrote: >>> The checking about MPX feature should be as follow: >>> >>> if (pcntxt_mask & XSTATE_EAGER) { >>> if (eagerfpu == DISABLE) { >>> pr_err("eagerfpu not present, disabling some >> xstate features: 0x%llx\n", >>> pcntxt_mask & >> XSTATE_EAGER); >>> pcntxt_mask &= ~XSTATE_EAGER; } else { eagerfpu >>> = ENABLE; >>> } >>> } >>> This patch was merged into kernel the ending of last year >>> (https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/com >>> mi >>> t/?id=e7d820a5e549b3eb6c3f9467507566565646a669 ) >> >> Should we be doing a clear_cpu_cap(X86_FEATURE_MPX) in here? >> >> This isn't major, but I can't _ever_ imagine a user being able to >> track down why MPX is not working from this message. Should we >> spruce it up somehow? > > Maybe. If the error log "disabling some xstate features:" is changed > to "disabling MPX xstate features:", do you think it is OK? That's better. Is it really disabling MPX, though? And shouldn't we clear the cpu feature bit too? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org