From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH 2/2] net: spider_net: avoid using signed char for bitops Date: Fri, 03 Oct 2014 17:15:05 +0200 Message-ID: <9201792.OAu7xPjvdN@wuerfel> References: <1412348517-20352-1-git-send-email-antoine.tenart@free-electrons.com> <1412348517-20352-4-git-send-email-antoine.tenart@free-electrons.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: Antoine Tenart , dan.carpenter@oracle.com, kou.ishizaki@toshiba.co.jp, jens@de.ibm.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: linux-arm-kernel@lists.infradead.org Return-path: Received: from mout.kundenserver.de ([212.227.17.13]:55571 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753679AbaJCPPM (ORCPT ); Fri, 3 Oct 2014 11:15:12 -0400 In-Reply-To: <1412348517-20352-4-git-send-email-antoine.tenart@free-electrons.com> Sender: netdev-owner@vger.kernel.org List-ID: On Friday 03 October 2014 17:01:56 Antoine Tenart wrote: > Signedness bugs may occur when using signed char for bitops, > depending on if the highest bit is ever used. > > Signed-off-by: Antoine Tenart > It's probably worth mentioning here that this cannot happen in this driver because it's only used in one powerpc-specific chip, and 'char' is always 'unsigned' on powerpc. Arnd