Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755869AbYAGKel (ORCPT ); Mon, 7 Jan 2008 05:34:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753902AbYAGKed (ORCPT ); Mon, 7 Jan 2008 05:34:33 -0500 Received: from ebiederm.dsl.xmission.com ([166.70.28.69]:51305 "EHLO ebiederm.dsl.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753217AbYAGKec (ORCPT ); Mon, 7 Jan 2008 05:34:32 -0500 From: ebiederm@xmission.com (Eric W. Biederman) To: Al Viro Cc: Tejun Heo , Gabor Gombas , Dave Young , linux-kernel@vger.kernel.org, bluez-devel@lists.sourceforge.net, Greg KH Subject: Re: [Bluez-devel] Oops involving RFCOMM and sysfs References: <20080102151642.GA7273@boogie.lpds.sztaki.hu> <20080105075039.GF27894@ZenIV.linux.org.uk> <477F9481.2040505@gmail.com> <20080105194510.GK27894@ZenIV.linux.org.uk> <478037F8.8020103@gmail.com> <47819079.3000606@gmail.com> <4781EE20.6070701@gmail.com> <4781EE5D.1000105@gmail.com> <20080107092256.GX27894@ZenIV.linux.org.uk> Date: Mon, 07 Jan 2008 03:33:38 -0700 In-Reply-To: <20080107092256.GX27894@ZenIV.linux.org.uk> (Al Viro's message of "Mon, 7 Jan 2008 09:22:56 +0000") Message-ID: User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1355 Lines: 31 Al Viro writes: > On Mon, Jan 07, 2008 at 06:18:21PM +0900, Tejun Heo wrote: >> Tejun Heo wrote: >> > Eric W. Biederman wrote: >> >>> That said, the mechanism is a bit too fragile. sysfs currently ensures >> >>> that dentry/inode point to the associated sysfs_dirent. This is mainly >> >>> remanent of conversion from previous VFS based implementation. I think >> >>> the right thing to do here is to make sysfs behave like other proper >> >>> distributed filesystems using d_revalidate. >> >> Huh? We still need something like sysfs_get_dentry to find the dentries >> >> for the rename or move operation. So we can call d_move. >> > >> > Ah... right. Thanks. :-) >> >> On the second thought, can't those too be dealt with d_revalidate? > > FVO "dealt with" as pleasant and efficient as using coarse whetstone > to deal with caries. Or to say it another way. The linux VFS requires dentries to be preserved and used as long as we can. dropping them early causes some weird nasties to show up, in particular it totally messes up mounting other filesystems on top. Eric -- 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/