From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755165AbYFYI53 (ORCPT ); Wed, 25 Jun 2008 04:57:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751657AbYFYI5U (ORCPT ); Wed, 25 Jun 2008 04:57:20 -0400 Received: from mx0.towertech.it ([213.215.222.73]:36469 "HELO mx0.towertech.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751085AbYFYI5T (ORCPT ); Wed, 25 Jun 2008 04:57:19 -0400 Date: Wed, 25 Jun 2008 10:57:17 +0200 From: Alessandro Zummo To: rtc-linux@googlegroups.com Cc: david-b@pacbell.net, lkml , Alan Cox , Jonathan Corbet , akpm@linux-foundation.org Subject: Re: [rtc-linux] [PATCH] rtc: remove BKL for ioctl() Message-ID: <20080625105717.2d9f30b2@i1501.lan.towertech.it> In-Reply-To: <200806221955.42597.david-b@pacbell.net> References: <200806221955.42597.david-b@pacbell.net> Organization: Tower Technologies X-Mailer: Sylpheed X-This-Is-A-Real-Message: Yes Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 22 Jun 2008 19:55:42 -0700 David Brownell wrote: > Remove implicit use of BKL in ioctl() from the RTC framework. > > Instead, the rtc->ops_lock is used. That's the same lock that already > protects the RTC operations when they're issued through the exported > rtc_*() calls in drivers/rtc/interface.c ... making this a bugfix, not > just a cleanup, since both ioctl calls and set_alarm() need to update > IRQ enable flags and that implies a common lock (which RTC drivers as > a rule do not provide on their own). > > A new comment at the declaration of "struct rtc_class_ops" summarizes > current locking rules. It's not clear to me that the exceptions listed > there should exist ... if not, those are pre-existing problems which can > be fixed in a patch that doesn't relate to BKL removal. > > Signed-off-by: David Brownell Acked-by: Alessandro Zummo -- Best regards, Alessandro Zummo, Tower Technologies - Torino, Italy http://www.towertech.it