Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755817AbZJNSLw (ORCPT ); Wed, 14 Oct 2009 14:11:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755663AbZJNSLv (ORCPT ); Wed, 14 Oct 2009 14:11:51 -0400 Received: from earthlight.etchedpixels.co.uk ([81.2.110.250]:47120 "EHLO www.etchedpixels.co.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755631AbZJNSLu (ORCPT ); Wed, 14 Oct 2009 14:11:50 -0400 Date: Wed, 14 Oct 2009 19:12:23 +0100 From: Alan Cox To: Thomas Gleixner Cc: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, gregkh@suse.de, linux-tip-commits@vger.kernel.org Subject: Re: [tip:bkl/drivers] drivers: Remove BKL from misc_open Message-ID: <20091014191223.35ba4004@lxorguk.ukuu.org.uk> In-Reply-To: References: <20091010153349.237173041@linutronix.de> <20091014171249.57dcdcfc@lxorguk.ukuu.org.uk> X-Mailer: Claws Mail 3.7.2 (GTK+ 2.14.7; x86_64-redhat-linux-gnu) 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 Content-Length: 1530 Lines: 39 On Wed, 14 Oct 2009 18:16:58 +0200 (CEST) Thomas Gleixner wrote: > on Wed, 14 Oct 2009, Alan Cox wrote: > > On Wed, 14 Oct 2009 15:47:39 GMT > > tip-bot for Thomas Gleixner wrote: > > > > > Commit-ID: 40b798efe3460797a4ac928ee2e038774e2758eb > > > Gitweb: http://git.kernel.org/tip/40b798efe3460797a4ac928ee2e038774e2758eb > > > Author: Thomas Gleixner > > > AuthorDate: Sat, 10 Oct 2009 15:35:43 +0000 > > > Committer: Thomas Gleixner > > > CommitDate: Wed, 14 Oct 2009 17:33:32 +0200 > > > > > > drivers: Remove BKL from misc_open > > > > > > misc_open() is already serialized with misc_mtx. Remove the BKL > > > locking which got there via the BKL pushdown. > > > > NAK. > > > > You can't simply assume the mutex is enough - you have to either push it > > down or review *every* possible called point below the lock_kernel take. > > > > In this case the open method of the misc devices below sometimes uses the > > BKL. > > The BKL got pushed down into the open methods of misc dev users and we > do not need to take it twice in a row, right ? Then the comment is misleading and you need to document that you've already pushed the BKL down into each user and checked them. Alan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/