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[209.132.180.67]) by mx.google.com with ESMTP id 1si4767994plr.189.2019.01.24.00.10.57; Thu, 24 Jan 2019 00:11:12 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b="ZEkD/omu"; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727386AbfAXIK2 (ORCPT + 99 others); Thu, 24 Jan 2019 03:10:28 -0500 Received: from mail.kernel.org ([198.145.29.99]:54386 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726046AbfAXIK2 (ORCPT ); Thu, 24 Jan 2019 03:10:28 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (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 8738621872; Thu, 24 Jan 2019 08:10:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548317427; bh=mVuhrQqk7Q0zWlxIFBTAwmH57rC+LNUGq0bYNV+P8nY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZEkD/omuTC/6WRsTLYnibk+sJ8XC+aSzvbF+D1UtelBBhWFwJCz4p3BgG898PP/WK EQqKpEKsH1ZCIh3xFKyM4r1WaPA8pegt/aOxYMcbdJRPPz7va8v2Z7lHYQ/DD8I6Zc TL6esem5HPhSos0hjBMX2YhzVQlPCdBuq/WP6cMI= Date: Thu, 24 Jan 2019 09:10:24 +0100 From: Greg KH To: Kees Cook Cc: Jani Nikula , Edwin Zimmerman , dev@openvswitch.org, Ard Biesheuvel , Network Development , intel-gfx@lists.freedesktop.org, linux-usb@vger.kernel.org, LKML , Maling list - DRI developers , Linux-MM , linux-security-module , Kernel Hardening , intel-wired-lan@lists.osuosl.org, "linux-fsdevel@vger.kernel.org" , xen-devel , Laura Abbott , linux-kbuild , Alexander Popov Subject: Re: [Intel-gfx] [PATCH 1/3] treewide: Lift switch variables out of switches Message-ID: <20190124081024.GA1108@kroah.com> References: <20190123110349.35882-1-keescook@chromium.org> <20190123110349.35882-2-keescook@chromium.org> <20190123115829.GA31385@kroah.com> <874l9z31c5.fsf@intel.com> <000001d4b32a$845e06e0$8d1a14a0$@211mainstreet.net> <87va2f1int.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.11.2 (2019-01-07) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 24, 2019 at 07:55:51AM +1300, Kees Cook wrote: > On Thu, Jan 24, 2019 at 4:44 AM Jani Nikula wrote: > > > > On Wed, 23 Jan 2019, Edwin Zimmerman wrote: > > > On Wed, 23 Jan 2019, Jani Nikula wrote: > > >> On Wed, 23 Jan 2019, Greg KH wrote: > > >> > On Wed, Jan 23, 2019 at 03:03:47AM -0800, Kees Cook wrote: > > >> >> Variables declared in a switch statement before any case statements > > >> >> cannot be initialized, so move all instances out of the switches. > > >> >> After this, future always-initialized stack variables will work > > >> >> and not throw warnings like this: > > >> >> > > >> >> fs/fcntl.c: In function ‘send_sigio_to_task’: > > >> >> fs/fcntl.c:738:13: warning: statement will never be executed [-Wswitch-unreachable] > > >> >> siginfo_t si; > > >> >> ^~ > > >> > > > >> > That's a pain, so this means we can't have any new variables in { } > > >> > scope except for at the top of a function? > > Just in case this wasn't clear: no, it's just the switch statement > before the first "case". I cannot imagine how bad it would be if we > couldn't have block-scoped variables! Heh. :) Sorry, it was not clear at first glance. So no more objection from me for this change. greg k-h