From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750902Ab3KBEQu (ORCPT ); Sat, 2 Nov 2013 00:16:50 -0400 Received: from forward12.mail.yandex.net ([95.108.130.94]:48181 "EHLO forward12.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750707Ab3KBEQt (ORCPT ); Sat, 2 Nov 2013 00:16:49 -0400 X-Greylist: delayed 362 seconds by postgrey-1.27 at vger.kernel.org; Sat, 02 Nov 2013 00:16:49 EDT From: =?koi8-r?B?8tXT1MHGwSDk1sHN1dLByM3F1M/X?= Envelope-From: drustafa@yandex.ru To: Andrew Morton Cc: Michal Nazarewicz , "linux-kernel@vger.kernel.org" In-Reply-To: <20131101123041.d08adc9739cf6e733d822770@linux-foundation.org> References: <5083d6c8452b765cb33acdf03fa9b20b1d15c452.1382788496.git.mina86@mina86.com> <20131030155938.0f5416fe3c5c2cbd3f9cd319@linux-foundation.org> <212981383321699@web5m.yandex.ru> <20131101123041.d08adc9739cf6e733d822770@linux-foundation.org> Subject: Re: [PATCH] drivers: w1: make w1_slave::flags long to avoid casts MIME-Version: 1.0 Message-Id: <7061383365433@web15j.yandex.ru> X-Mailer: Yamail [ http://yandex.ru ] 5.0 Date: Sat, 02 Nov 2013 08:10:33 +0400 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=koi8-r Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi 01.11.2013, 23:30, "Andrew Morton" : > set_bit() operates on longs. šSo if we do > > struct foo { > ššššššššu32 a; > ššššššššu32 b; > } f; > > šššššššš... > ššššššššset_bit(0, (long *)&f.a); > šššššššš... > > then we'll scribble on f.b on a big-endian 64-bit machine. Argh, why would we just don't do that? Its in-memory field, it can be anything, I wouldn't be surprised if it even can be non-atomic because of proper locks already being held