From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S968201AbcA1DcC (ORCPT ); Wed, 27 Jan 2016 22:32:02 -0500 Received: from ozlabs.org ([103.22.144.67]:48934 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965569AbcA1DcA (ORCPT ); Wed, 27 Jan 2016 22:32:00 -0500 Message-ID: <1453951918.4108.1.camel@ellerman.id.au> Subject: Re: [PATCH v6 0/9] ftrace with regs + live patching for ppc64 LE (ABI v2) From: Michael Ellerman To: Balbir Singh , Torsten Duwe Cc: Steven Rostedt , Jiri Kosina , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, live-patching@vger.kernel.org Date: Thu, 28 Jan 2016 14:31:58 +1100 In-Reply-To: <20160128134157.1ac3d344@cotter.ozlabs.ibm.com> References: <20160125170459.14DB7692CE@newverein.lst.de> <20160127215112.080eec56@cotter.ozlabs.ibm.com> <20160127121904.GB32095@lst.de> <20160128134157.1ac3d344@cotter.ozlabs.ibm.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.16.5-1ubuntu3.1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2016-01-28 at 13:41 +1100, Balbir Singh wrote: > On Wed, 27 Jan 2016 13:19:04 +0100 > Torsten Duwe wrote: > > > Thanks! Make sure you use a compiler that can disable -mprofile-kernel with "notrace". > > gcc-6? I have gcc-5.2.1 That should work. But that's a good point. We need to have some Makefile logic to only enable -mprofile-kernel when it's known to work, ie. for versions where the notrace fix is in. Looking at GCC history it looks like the fix is in 4.9.0 and anything later. But a version check doesn't work with patched distro/vendor toolchains. So we probably need some sort of runtime check. cheers