linux-ext4 - Re: ext3: slow symlink corruption on umount...

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Date:	Wed, 29 Oct 2008 15:36:33 -0500
From:	Eric Sandeen <sandeen@...hat.com>
To:	Arthur Jones <ajones@...erbed.com>
CC:	"linux-ext4@...r.kernel.org" <linux-ext4@...r.kernel.org>,
	sct@...hat.com, akpm@...ux-foundation.org,
	linux-kernel@...r.kernel.org
Subject: Re: ext3: slow symlink corruption on umount...

Arthur Jones wrote:
> This one's turning out to be a slippery fish.
> I have found that the corruption appears to
> be due to ->writepage() not getting called at all
> for any of the long symlinks...
> 
> Ring any bells anyone?  Any ideas where to look
> or what to test?  This is my first foray into
> ext3 and I could definitely use some expert advice...
> 
> Arthur


Sorry for the silence, this is a nice bug you've found :)

I can reproduce this at least, with this script:

#!/bin/bash

umount /mnt/test2
mount /dev/sdb4 /mnt/test2
rm -f /mnt/test2/*
dd if=/dev/zero of=/mnt/test2/bigfile bs=1M count=512
touch
/mnt/test2/thisisveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryverylongfilename
ln -s
/mnt/test2/thisisveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryverylongfilename
/mnt/test2/link
umount /mnt/test2
mount /dev/sdb4 /mnt/test2
ls /mnt/test2/
umount /mnt/test2

I'll look into it ...

-Eric
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