From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752107AbdF3N0n (ORCPT ); Fri, 30 Jun 2017 09:26:43 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49014 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751690AbdF3N0l (ORCPT ); Fri, 30 Jun 2017 09:26:41 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 2CF027A162 Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=jpoimboe@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 2CF027A162 Date: Fri, 30 Jun 2017 08:26:39 -0500 From: Josh Poimboeuf To: Ingo Molnar Cc: x86@kernel.org, linux-kernel@vger.kernel.org, live-patching@vger.kernel.org, Linus Torvalds , Andy Lutomirski , Jiri Slaby , "H. Peter Anvin" , Peter Zijlstra Subject: Re: [PATCH v2 3/8] objtool: stack validation 2.0 Message-ID: <20170630132639.756g3kvz6sgmfjwz@treble> References: <678bd94c0566c6129bcc376cddb259c4c5633004.1498659915.git.jpoimboe@redhat.com> <20170630083203.7n5kbwieuoyjoov4@gmail.com> <20170630132336.fg4ndgoogam6kdk6@treble> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20170630132336.fg4ndgoogam6kdk6@treble> User-Agent: Mutt/1.6.0.1 (2016-04-01) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Fri, 30 Jun 2017 13:26:41 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 30, 2017 at 08:23:36AM -0500, Josh Poimboeuf wrote: > On Fri, Jun 30, 2017 at 10:32:03AM +0200, Ingo Molnar wrote: > > > > * Josh Poimboeuf wrote: > > > > > This is a major rewrite of objtool. Instead of only tracking frame > > > pointer changes, it now tracks all stack-related operations, including > > > all register saves/restores. > > > > > > In addition to making stack validation more robust, this also paves the > > > way for undwarf generation. > > > > > > Signed-off-by: Josh Poimboeuf > > > > Note, I have applied the first 3 patches, and got a bunch of new warnings on x86 > > 64-bit allmodconfig: > > > > arch/x86/kernel/alternative.o: warning: objtool: do_sync_core()+0x1b: unsupported instruction in callable function > > arch/x86/kernel/alternative.o: warning: objtool: text_poke()+0x1a8: unsupported instruction in callable function > > arch/x86/kernel/ftrace.o: warning: objtool: do_sync_core()+0x16: unsupported instruction in callable function > > arch/x86/kernel/cpu/mcheck/mce.o: warning: objtool: machine_check_poll()+0x166: unsupported instruction in callable function > > arch/x86/kernel/cpu/mcheck/mce.o: warning: objtool: do_machine_check()+0x147: unsupported instruction in callable function > > > > (That's the vmlinux build - plus 4 more warnings in the modules build.) > > > > That's with GCC 5.3.1. > > > > Let me know if you need any more info. > > Hm, this is odd. I tried with GCC 5.3.0 (which should presumably be > almost identical to 5.3.1) and I don't see any warnings. Can you send > me one of the object files it's complaining about? Oh wait, never mind. Now that I'm actually reading the warnings, it makes sense. Those are warnings I fixed in a later patch in the series. I'll try to come up with something to fix those without pulling in the rest of the patches. -- Josh