From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4C59EC433DF for ; Wed, 22 Jul 2020 17:58:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2780B20B1F for ; Wed, 22 Jul 2020 17:58:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726685AbgGVR6k (ORCPT ); Wed, 22 Jul 2020 13:58:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:50674 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726666AbgGVR6k (ORCPT ); Wed, 22 Jul 2020 13:58:40 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 59D79208E4; Wed, 22 Jul 2020 17:58:38 +0000 (UTC) Date: Wed, 22 Jul 2020 13:58:36 -0400 From: Steven Rostedt To: Sami Tolvanen Cc: Peter Zijlstra , Masahiro Yamada , Will Deacon , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux , Kernel Hardening , linux-arch , linux-arm-kernel , linux-kbuild , LKML , linux-pci@vger.kernel.org, X86 ML , Josh Poimboeuf Subject: Re: [RFC][PATCH] objtool,x86_64: Replace recordmcount with objtool Message-ID: <20200722135829.7ca6fbc5@oasis.local.home> In-Reply-To: References: <20200624203200.78870-1-samitolvanen@google.com> <20200624203200.78870-5-samitolvanen@google.com> <20200624212737.GV4817@hirez.programming.kicks-ass.net> <20200624214530.GA120457@google.com> <20200625074530.GW4817@hirez.programming.kicks-ass.net> <20200625161503.GB173089@google.com> <20200625200235.GQ4781@hirez.programming.kicks-ass.net> <20200625224042.GA169781@google.com> <20200626112931.GF4817@hirez.programming.kicks-ass.net> <20200717133645.7816c0b6@oasis.local.home> <20200717140545.6f008208@oasis.local.home> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Mon, 20 Jul 2020 09:52:37 -0700 Sami Tolvanen wrote: > > Does x86 have a way to differentiate between the two that record mcount > > can check? > > I'm not sure if looking at the relocation alone is sufficient on x86, > we might also have to decode the instruction, which is what objtool > does. Did you have any thoughts on Peter's patch, or my initial > suggestion, which adds a __nomcount attribute to affected functions? There's a lot of code in this thread. Can you give me the message-id of Peter's patch in question. Thanks, -- Steve