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Sun, 22 Nov 2020 23:10:42 +0100 (CET) Date: Sun, 22 Nov 2020 23:10:40 +0100 From: Sam Ravnborg To: James Bottomley Message-ID: <20201122221040.GD566387@ravnborg.org> 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> MIME-Version: 1.0 In-Reply-To: <9b57fd4914b46f38d54087d75e072d6e947cb56d.camel@HansenPartnership.com> X-CMAE-Score: 0 X-CMAE-Analysis: v=2.3 cv=VafZwmh9 c=1 sm=1 tr=0 a=S6zTFyMACwkrwXSdXUNehg==:117 a=S6zTFyMACwkrwXSdXUNehg==:17 a=kj9zAlcOel0A:10 a=VwQbUJbxAAAA:8 a=pGLkceISAAAA:8 a=7T594MSkF3521FIrX4wA:9 a=CjuIK1q_8ugA:10 a=AjGcO6oz07-iQ99wixmX:22 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 2.78 on 10.11.54.3 X-loop: dm-devel@redhat.com X-Mailman-Approved-At: Mon, 23 Nov 2020 03:39:39 -0500 Cc: alsa-devel@alsa-project.org, bridge@lists.linux-foundation.org, 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, "Gustavo A. R. Silva" , 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, target-devel@vger.kernel.org, tipc-discussion@lists.sourceforge.net, linux-crypto@vger.kernel.org, patches@opensource.cirrus.com, Joe Perches , linux-integrity@vger.kernel.org, linux-usb@vger.kernel.org, x86@kernel.org, linux-hardening@vger.kernel.org Subject: Re: [dm-devel] [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 10.5.11.11 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 Hi James. > > > If none of the 140 patches here fix a real bug, and there is no > > > change to machine code then it sounds to me like a W=2 kind of a > > > warning. > > > > FWIW, this series has found at least one bug so far: > > https://lore.kernel.org/lkml/CAFCwf11izHF=g1mGry1fE5kvFFFrxzhPSM6qKAO8gxSp=Kr_CQ@mail.gmail.com/ > > > Well, it's a problem in an error leg, sure, but it's not a really > compelling reason for a 141 patch series, is it? All that fixing this > error will do is get the driver to print "oh dear there's a problem" > under four more conditions than it previously did. You are asking the wrong question here. Yuo should ask how many hours could have been saved by all the bugs people have been fighting with and then fixed *before* the code hit the kernel at all. My personal experience is that I, more than once, have had errors related to a missing break in my code. So this warnings is IMO a win. And if we are only ~100 patches to have it globally enabled then it is a no-brainer in my book. Sam -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel