From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Dave Young" Subject: Re: [PATCH 1/3][-mm] add class_reclassify macro Date: Tue, 27 May 2008 14:42:51 +0800 Message-ID: References: <20080520095553.GA3201@darkstar.te-china.tietoenator.com> <20080520030232.fc91b64e.akpm@linux-foundation.org> <20080520172139.GA11666@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: Received: from ti-out-0910.google.com ([209.85.142.188]:5665 "EHLO ti-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755571AbYE0Gmx (ORCPT ); Tue, 27 May 2008 02:42:53 -0400 Received: by ti-out-0910.google.com with SMTP id b6so1619951tic.23 for ; Mon, 26 May 2008 23:42:51 -0700 (PDT) In-Reply-To: <20080520172139.GA11666@kroah.com> Content-Disposition: inline Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Greg KH Cc: Andrew Morton , matthew@wil.cx, kay.sievers@vrfy.org, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org On Wed, May 21, 2008 at 1:21 AM, Greg KH wrote: > On Tue, May 20, 2008 at 03:02:32AM -0700, Andrew Morton wrote: >> On Tue, 20 May 2008 17:55:54 +0800 Dave Young wrote: >> >> > Converting class semaphore to mutex cause lockdep warnings due to >> > class_interface_register/unregister will possible call device_add/del >> >> Shouldn't we just fix that? > > Um, no, that's a "feature" that some types of hardware and interfaces > require. > > This is one reason I really don't like this type of conversion, it's > causing lots of problems for no known gain. > > So I would just recommend dropping this patch set, the current "convert > class semaphore to a mutex" patch in the -mm tree is already causing > lockdep warnings, and trying to do something like this isn't really > going to solve the root problem here. At last, I decide to give up. Andrew, I could not do more for this issue now, you can drop the conversion patch if there's no suitable fix from others. Thanks Dave