From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752986AbaB1QM5 (ORCPT ); Fri, 28 Feb 2014 11:12:57 -0500 Received: from terminus.zytor.com ([198.137.202.10]:44108 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751677AbaB1QM4 (ORCPT ); Fri, 28 Feb 2014 11:12:56 -0500 Message-ID: <5310B54F.3000709@zytor.com> Date: Fri, 28 Feb 2014 08:11:59 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: Jiri Olsa , Peter Zijlstra CC: linux-kernel@vger.kernel.org, Paul Mackerras , Ingo Molnar , Arnaldo Carvalho de Melo , Seiji Aguchi , Steven Rostedt , Vince Weaver Subject: Re: [PATCHv2] x86 trace: Fix page fault tracing bug References: <1393601620-13117-1-git-send-email-jolsa@redhat.com> <20140228154708.GI9987@twins.programming.kicks-ass.net> <20140228160526.GD1133@krava.brq.redhat.com> In-Reply-To: <20140228160526.GD1133@krava.brq.redhat.com> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/28/2014 08:05 AM, Jiri Olsa wrote: > On Fri, Feb 28, 2014 at 04:47:08PM +0100, Peter Zijlstra wrote: >> On Fri, Feb 28, 2014 at 04:33:40PM +0100, Jiri Olsa wrote: >> >> While I like the idea of just pushing up the CR2 read; the below does >> the read too late still, exception_enter() also has a tracepoint in. > > please check v2, thanks Is there any way something could come in even earlier (perhaps via __fentry__)? If so, do we need to hoist the reading of %cr2 all the way into assembly or something else? -hpa