From: Round Robinjp Subject: Re: flashing large eMMC partitions with ext4 Date: Wed, 3 Aug 2011 01:07:08 +0900 (JST) Message-ID: <20110802160715.3069.qmail@web4212.mail.ogk.yahoo.co.jp> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Cc: Andreas Dilger , Ted Ts'o , "linux-ext4@vger.kernel.org" To: Goldstein Amir Return-path: Received: from web4212.mail.ogk.yahoo.co.jp ([124.83.212.32]:23928 "HELO web4212.mail.ogk.yahoo.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754365Ab1HBQHU convert rfc822-to-8bit (ORCPT ); Tue, 2 Aug 2011 12:07:20 -0400 In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: Amir > > But after extending to 4G, e2fsck makes some complain. > > I guess this is not expected behaviour, is it? > > > > it is expected when you use the current resize2fs, > which does not respect the flex_bg layout, so new group block bitmaps > are allocated beyond the 1G border and initialized. So that means I have thrown away some important part of the filesystem when I did truncate -s 1G, isn't it? Will things go wrong if I flash this 1G image to my eMMC partition (without using Yongqiang's new 64bit resize patches)? I need to understand whether Yongqiang's patch is absolutely necessary for this purpose or just a good thing to have. > if you use Yongqiang's new 64bit resize patches, the final fsck won't complain. > unfortunately for you, those patches have not been merged to the kernel yet, > so you will have to either build your own ext4 module or wait at least until > kernel 3.2 is released to have it in mainline. As said above. > It is actually quite simple to fix the 1G image, so it will pass fsck > after truncate -s 4G. > All it takes it setting the BLOCK_UNINIT flag in groups 8-31 > this should be possible to do with debugfs (or write a small tool to do it). > if I have time, it will try it myself and post the instructions. OK, thanks in advance. Best Regards Round