From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751530AbaDWVq3 (ORCPT ); Wed, 23 Apr 2014 17:46:29 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:59612 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750980AbaDWVqZ (ORCPT ); Wed, 23 Apr 2014 17:46:25 -0400 Date: Wed, 23 Apr 2014 14:46:24 -0700 From: Andrew Morton To: Ian Kent Cc: autofs mailing list , Kernel Mailing List Subject: Re: [PATCH] autofs - fix lockref lookup Message-Id: <20140423144624.716f325d454f9debd97bef15@linux-foundation.org> In-Reply-To: <20140423052035.5999.69412.stgit@perseus.fritz.box> References: <20140423052035.5999.69412.stgit@perseus.fritz.box> X-Mailer: Sylpheed 3.2.0beta5 (GTK+ 2.24.10; x86_64-pc-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 On Wed, 23 Apr 2014 13:20:36 +0800 Ian Kent wrote: > autofs needs to be able to see private data dentry flags for > its dentrys that are being created but not yet hashed and for > its dentys that have been rmdir()ed but not yet freed. It > needs to do this so it can block processes in these states > until a status has been returned to indicate the given > operation is complete. > > It does this by keeping two lists, active and expring, of > dentrys in this state and uses ->d_release() to keep them > stable while it checks the reference count to determine > if they should be used. > > But with the recent lockref changes dentrys being freed > sometimes don't transition to a reference count of 0 before > being freed so autofs can occassionally use a dentry that > is invalid which can lead to a panic. What's the value of "recent"? I assume 3.14 is OK?