From: Thiemo Nagel Subject: Re: [PATCH] Add checks to validate extent entries. Date: Mon, 09 Feb 2009 11:26:12 +0100 Message-ID: <499004C4.9040305@ph.tum.de> References: <20090207173239.GA25942@skywalker> <1234036882-30656-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: tytso@mit.edu, linux-ext4@vger.kernel.org To: "Aneesh Kumar K.V" Return-path: Received: from hamlet.e18.physik.tu-muenchen.de ([129.187.154.223]:42698 "EHLO hamlet.e18.physik.tu-muenchen.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752686AbZBIK0P (ORCPT ); Mon, 9 Feb 2009 05:26:15 -0500 In-Reply-To: <1234036882-30656-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Aneesh Kumar K.V wrote: > This patch adds check to validate the extent entries along > with extent headers. Should handle crash with corrupt filesystem. While your patch probably decreases the average number of checks that are done, it makes single random accesses quite expensive since always complete extent blocks are checked at once, even if just a single pblock is accessed. No idea whether there are workloads which have that as a typical access pattern... Kind regards, Thiemo