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 AD946C10DCE for ; Wed, 18 Mar 2020 18:24:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 86E912077E for ; Wed, 18 Mar 2020 18:24:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="aFvqpM0Q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726623AbgCRSYA (ORCPT ); Wed, 18 Mar 2020 14:24:00 -0400 Received: from us-smtp-delivery-74.mimecast.com ([63.128.21.74]:60440 "EHLO us-smtp-delivery-74.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726596AbgCRSYA (ORCPT ); Wed, 18 Mar 2020 14:24:00 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1584555839; 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=1BhPTAKqSYELkcumcDrePcKLFULRe/8k/IRbjYPD+Us=; b=aFvqpM0Q7oB0vA5/KHOmtj/bmwvRddSdNus3bGEKu2J0vq+u1XY2XRwfqE3ZnUMnpGTgPt 6o93AuZLEemxJcUay223/pZ3Q9hRDAWuDX/mc/BDjWelq6dOyaBEJQMeHWma4S9sL7/6BB Pd2yYK238x0U6zbnwxED4MY+f2B+hhQ= 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-304-Gr67u16UMG-dw6JrsGdxxg-1; Wed, 18 Mar 2020 14:23:57 -0400 X-MC-Unique: Gr67u16UMG-dw6JrsGdxxg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 50D95107ACCA; Wed, 18 Mar 2020 18:23:56 +0000 (UTC) Received: from treble (unknown [10.10.110.4]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C08E119756; Wed, 18 Mar 2020 18:23:54 +0000 (UTC) Date: Wed, 18 Mar 2020 13:23:52 -0500 From: Josh Poimboeuf To: Randy Dunlap Cc: Stephen Rothwell , Linux Next Mailing List , Linux Kernel Mailing List , Peter Zijlstra , Kees Cook Subject: Re: linux-next: Tree for Mar 18 (objtool) Message-ID: <20200318182352.2dgwwl4ugbwndi4x@treble> References: <20200318220920.48df2e76@canb.auug.org.au> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Sender: linux-next-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-next@vger.kernel.org On Wed, Mar 18, 2020 at 09:48:01AM -0700, Randy Dunlap wrote: > On 3/18/20 4:09 AM, Stephen Rothwell wrote: > > Hi all, > > > > Changes since 20200317: > > > > Hi, > > For some reason, the attached .config file generates over 350 objtool warnings. > There are all "unreachable instruction" warnings. > > Here is a small sample: > > mm/page-writeback.o: warning: objtool: __set_page_dirty_nobuffers()+0x25b: unreachable instruction > kernel/sched/fair.o: warning: objtool: load_balance()+0x54c: unreachable instruction > kernel/power/process.o: warning: objtool: freeze_kernel_threads()+0x115: unreachable instruction > mm/readahead.o: warning: objtool: read_cache_pages_invalidate_page()+0x1b5: unreachable instruction > kernel/power/suspend.o: warning: objtool: suspend_devices_and_enter()+0x101f: unreachable instruction > kernel/sched/rt.o: warning: objtool: dequeue_top_rt_rq()+0x67: unreachable instruction This seems to be caused by 545ed6816b72 ("ubsan: add trap instrumentation option") Kees, any idea why that commit causes at least some BUG() statements to output an extra UD2? -- Josh