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,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 81842C2D0E4 for ; Tue, 24 Nov 2020 08:54:01 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D1C7C2075A for ; Tue, 24 Nov 2020 08:54:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D1C7C2075A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=tempfail smtp.mailfrom=dm-devel-bounces@redhat.com 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-516-iYoa80z_PnyuPJItI_-kfw-1; Tue, 24 Nov 2020 03:53:57 -0500 X-MC-Unique: iYoa80z_PnyuPJItI_-kfw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4975D10151E9; Tue, 24 Nov 2020 08:53:53 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0AFDD60C4D; Tue, 24 Nov 2020 08:53:53 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 8AEEC4A7C6; Tue, 24 Nov 2020 08:53:50 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 0AND3mU6024911 for ; Mon, 23 Nov 2020 08:03:48 -0500 Received: by smtp.corp.redhat.com (Postfix) id A4D215D208; Mon, 23 Nov 2020 13:03:48 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast03.extmail.prod.ext.rdu2.redhat.com [10.11.55.19]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 9E7A45D206 for ; Mon, 23 Nov 2020 13:03:46 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-1.mimecast.com [207.211.31.81]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 601AB811E8F for ; Mon, 23 Nov 2020 13:03:46 +0000 (UTC) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-451-JcxkM3j_NGihY2o613RXiw-1; Mon, 23 Nov 2020 08:03:43 -0500 X-MC-Unique: JcxkM3j_NGihY2o613RXiw-1 Received: from embeddedor (187-162-31-110.static.axtel.net [187.162.31.110]) (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 191D120758; Mon, 23 Nov 2020 13:03:35 +0000 (UTC) Date: Mon, 23 Nov 2020 07:03:48 -0600 From: "Gustavo A. R. Silva" To: James Bottomley Message-ID: <20201123130348.GA3119@embeddedor> References: <20201120105344.4345c14e@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <202011201129.B13FDB3C@keescook> <20201120115142.292999b2@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <202011220816.8B6591A@keescook> <9b57fd4914b46f38d54087d75e072d6e947cb56d.camel@HansenPartnership.com> <0147972a72bc13f3629de8a32dee6f1f308994b5.camel@HansenPartnership.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-loop: dm-devel@redhat.com X-Mailman-Approved-At: Tue, 24 Nov 2020 03:53:49 -0500 Cc: alsa-devel@alsa-project.org, bridge@lists.linux-foundation.org, target-devel@vger.kernel.org, Greg KH , linux-iio@vger.kernel.org, linux-wireless@vger.kernel.org, linux-mmc@vger.kernel.org, linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, virtualization@lists.linux-foundation.org, linux-mm@kvack.org, linux-ide@vger.kernel.org, dm-devel@redhat.com, keyrings@vger.kernel.org, linux-mtd@lists.infradead.org, GR-everest-linux-l2@marvell.com, wcn36xx@lists.infradead.org, linux-i3c@lists.infradead.org, linux1394-devel@lists.sourceforge.net, linux-afs@lists.infradead.org, linux-watchdog@vger.kernel.org, devel@driverdev.osuosl.org, linux-cifs@vger.kernel.org, rds-devel@oss.oracle.com, linux-scsi@vger.kernel.org, linux-acpi@vger.kernel.org, linux-rdma@vger.kernel.org, oss-drivers@netronome.com, linux-atm-general@lists.sourceforge.net, ceph-devel@vger.kernel.org, amd-gfx@lists.freedesktop.org, linux-stm32@st-md-mailman.stormreply.com, cluster-devel@redhat.com, usb-storage@lists.one-eyed-alien.net, coreteam@netfilter.org, intel-wired-lan@lists.osuosl.org, linux-input@vger.kernel.org, Miguel Ojeda , Jakub Kicinski , linux-ext4@vger.kernel.org, netfilter-devel@vger.kernel.org, linux-media@vger.kernel.org, Kees Cook , selinux@vger.kernel.org, linux-arm-msm@vger.kernel.org, intel-gfx@lists.freedesktop.org, linux-sctp@vger.kernel.org, reiserfs-devel@vger.kernel.org, linux-geode@lists.infradead.org, linux-block@vger.kernel.org, linux-gpio@vger.kernel.org, op-tee@lists.trustedfirmware.org, linux-mediatek@lists.infradead.org, xen-devel@lists.xenproject.org, drbd-dev@tron.linbit.com, linux-hams@vger.kernel.org, Nathan Chancellor , linux-can@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-hwmon@vger.kernel.org, Nick Desaulniers , linux-nfs@vger.kernel.org, GR-Linux-NIC-Dev@marvell.com, nouveau@lists.freedesktop.org, netdev@vger.kernel.org, linux-decnet-user@lists.sourceforge.net, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-security-module@vger.kernel.org, linux-usb@vger.kernel.org, tipc-discussion@lists.sourceforge.net, linux-crypto@vger.kernel.org, Jonathan Cameron , patches@opensource.cirrus.com, Joe Perches , linux-integrity@vger.kernel.org, x86@kernel.org, linux-hardening@vger.kernel.org Subject: Re: [dm-devel] [Intel-wired-lan] [PATCH 000/141] Fix fall-through warnings for Clang X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Sun, Nov 22, 2020 at 11:53:55AM -0800, James Bottomley wrote: > On Sun, 2020-11-22 at 11:22 -0800, Joe Perches wrote: > > On Sun, 2020-11-22 at 11:12 -0800, James Bottomley wrote: > > > On Sun, 2020-11-22 at 10:25 -0800, Joe Perches wrote: > > > > On Sun, 2020-11-22 at 10:21 -0800, James Bottomley wrote: > > > > > Please tell me our reward for all this effort isn't a single > > > > > missing error print. > > > > > > > > There were quite literally dozens of logical defects found > > > > by the fallthrough additions. Very few were logging only. > > > > > > So can you give us the best examples (or indeed all of them if > > > someone is keeping score)? hopefully this isn't a US election > > > situation ... > > > > Gustavo? Are you running for congress now? > > > > https://lwn.net/Articles/794944/ > > That's 21 reported fixes of which about 50% seem to produce no change > in code behaviour at all, a quarter seem to have no user visible effect > with the remaining quarter producing unexpected errors on obscure > configuration parameters, which is why no-one really noticed them > before. The really important point here is the number of bugs this has prevented and will prevent in the future. See an example of this, below: https://lore.kernel.org/linux-iio/20190813135802.GB27392@kroah.com/ This work is still relevant, even if the total number of issues/bugs we find in the process is zero (which is not the case). "The sucky thing about doing hard work to deploy hardening is that the result is totally invisible by definition (things not happening) [..]" - Dmitry Vyukov Thanks -- Gustavo -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel