From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754722AbYEaIWZ (ORCPT ); Sat, 31 May 2008 04:22:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751774AbYEaIWN (ORCPT ); Sat, 31 May 2008 04:22:13 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:40991 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751566AbYEaIWL (ORCPT ); Sat, 31 May 2008 04:22:11 -0400 Date: Sat, 31 May 2008 04:22:10 -0400 From: Christoph Hellwig To: Miklos Szeredi Cc: linux-fsdevel@vger.kernel.org, hch@infradead.org, viro@ZenIV.linux.org.uk, linux-kernel@vger.kernel.org, Andreas Gruenbacher , John Johansen Subject: Re: [patch 3/8] Make d_path() consistent across mount operations Message-ID: <20080531082210.GD24135@infradead.org> References: <20080529113245.450308367@szeredi.hu> <20080529113310.608958055@szeredi.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080529113310.608958055@szeredi.hu> User-Agent: Mutt/1.5.17 (2007-11-01) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 29, 2008 at 01:32:48PM +0200, Miklos Szeredi wrote: > The path that __d_path() computes can become slightly inconsistent when it > races with mount operations: it grabs the vfsmount_lock when traversing mount > points but immediately drops it again, only to re-grab it when it reaches the > next mount point. The result is that the filename computed is not always > consisent, and the file may never have had that name. (This is unlikely, but > still possible.) > > Fix this by grabbing the vfsmount_lock for the whole duration of > __d_path(). Looks good, and lock holding times shouldn't be a problem either.