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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 5C373C43331 for ; Fri, 27 Mar 2020 03:55:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2A47D206F6 for ; Fri, 27 Mar 2020 03:55:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="h2N8pfD/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727719AbgC0DzU (ORCPT ); Thu, 26 Mar 2020 23:55:20 -0400 Received: from us-smtp-delivery-74.mimecast.com ([216.205.24.74]:49567 "EHLO us-smtp-delivery-74.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727708AbgC0DzU (ORCPT ); Thu, 26 Mar 2020 23:55:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1585281319; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=jbUZbS8mLCFbjFYPv9xZPzpFZFr2HhSo9vjkHm0xqCQ=; b=h2N8pfD/AWfFpEePUi91ZPJxUhzGcb2vHwYpKIGZHweRzSQJ/ZAdhQJ96CdJwtqfpbtsGj g6vSNACa6xBdoPIm40Hv6EZIgyLhNVaEgekwEtb/wiFTOJDSmiNLfNGxYfTJDdINcHhmAF 9GpCvbReYMWLm6WFHuF8jTaVj2itDF8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-359-FV5CEmW1NISu3HHUcOuYjQ-1; Thu, 26 Mar 2020 23:55:17 -0400 X-MC-Unique: FV5CEmW1NISu3HHUcOuYjQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0194518C43D6; Fri, 27 Mar 2020 03:55:16 +0000 (UTC) Received: from treble (unknown [10.10.110.12]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5792D9B93E; Fri, 27 Mar 2020 03:55:14 +0000 (UTC) Date: Thu, 26 Mar 2020 22:55:11 -0500 From: Josh Poimboeuf To: Kees Cook Cc: Peter Zijlstra , Randy Dunlap , Stephen Rothwell , Linux Next Mailing List , Linux Kernel Mailing List Subject: Re: linux-next: Tree for Mar 18 (objtool) Message-ID: <20200327035511.7lqv5ij4e745vzv2@treble> References: <20200319174028.azzaisoj5gbss7zk@treble> <20200319174550.4wpx4j357nw67nzz@treble> <20200320082613.GA20696@hirez.programming.kicks-ass.net> <202003201131.9B688BC@keescook> <20200324164433.qusyu5h7ykx3f2bu@treble> <202003241105.4707F983@keescook> <20200324222406.zg6hylzqux353jhq@treble> <202003252251.771EF5EC5F@keescook> <20200326163110.n35lxcgkfcar7vd5@treble> <202003261133.814BEE9F@keescook> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <202003261133.814BEE9F@keescook> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Sender: linux-next-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-next@vger.kernel.org On Thu, Mar 26, 2020 at 11:36:10AM -0700, Kees Cook wrote: > On Thu, Mar 26, 2020 at 11:31:10AM -0500, Josh Poimboeuf wrote: > > On Wed, Mar 25, 2020 at 10:57:02PM -0700, Kees Cook wrote: > > > > In the meantime I can still change objtool to ignore unreachable UD2s if > > > > there aren't any better ideas. > > > > > > It'll still need the objtool change for CONFIG_UBSAN_TRAP, though based on > > > the clang bug discussion, I'll probably _also_ be adding CONFIG_UBSAN_WARN > > > which won't have an unreachable (and won't bloat the kernel). Testing > > > still under way... it is possible that CONFIG_UBSAN_TRAP will go away > > > in the future, though. If that happens, should I also remove the change > > > at that time? > > > > I'll go ahead and make the patch and post it soon. It should be pretty > > trivial. We can always revert it if CONFIG_UBSAN_TRAP goes away. > > Awesome, thanks very much. After digging into the WARN-style option, > it seems that TRAP is unlikely to go away because it's Clang only; > GCC doesn't support the "minimal runtime" option. Yay compilers. Oh well... > Anyway, I'll still get the WARN mode sent out. Thanks for looking at this; > can you CC me on the patch? I'm trying to get more familiar with objtool > so I don't have to bug you when objtool is angered by crazy stuff I do. ;) Will do. I know objtool tends to get in the way of adding cool features sometimes. More eyes on the objtool code are definitely welcome. -- Josh