From: Mark Lord Subject: Re: CONFIG_EXT4_USE_FOR_EXT23: rootfs shows as ext2 instead of ext4 Date: Wed, 13 Apr 2011 10:10:06 -0400 Message-ID: <4DA5AEBE.6060705@teksavvy.com> References: <4DA48AF4.5080803@teksavvy.com> <20110413004938.GE3682@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit To: Ted Ts'o , Linux Kernel , linux-ext4@vger.kernel.org Return-path: Received: from ironport2-out.teksavvy.com ([206.248.154.181]:62700 "EHLO ironport2-out.pppoe.ca" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756017Ab1DMOKH (ORCPT ); Wed, 13 Apr 2011 10:10:07 -0400 In-Reply-To: <20110413004938.GE3682@thunk.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 11-04-12 08:49 PM, Ted Ts'o wrote: > On Tue, Apr 12, 2011 at 01:25:08PM -0400, Mark Lord wrote: >> Ted et al. >> >> I've only just noticed this, so I have no idea how long it has been this way. >> >> When I build a kernel with CONFIG_EXT4_USE_FOR_EXT23=y and boot from it, >> the ext4 root filesystem shows up as "ext2" mode, rather than "ext4". >> >> This looks very wrong to me, and quite dangerous. > > It's a cosemtic bug, I agree, but I'm not sure why you consider it > dangerous. It is dangerous if it really has mounted an ext4 as ext2; the on-disk formats are not 100% compatible. I don't know what it is doing, so it looks quite dangerous. Perhaps it really did mount as ext4 though, in which case not. Thanks.