From: "Richard W.M. Jones" <rjones@redhat.com>
Subject: Re: Kernel 3.3.8 breaks accidental ext3 mount of extended partition
Date: Mon, 25 Jun 2012 12:34:57 +0100
Message-ID: <20120625113457.GA1289@amd.home.annexia.org>
References: <4FDEC3C2.4060909@secunet.com>
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Cc: jmoyer@redhat.com, linux-ext4@vger.kernel.org,
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To: Torsten Hilbrich <torsten.hilbrich@secunet.com>
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On Mon, Jun 18, 2012 at 07:59:30AM +0200, Torsten Hilbrich wrote:
> Hello,
> 
> a software that tries to mount each existing partition as ext3 file system started to fail when updating from v3.3.7 to v3.3.8.
> 
> The applications then hangs-up in the mount syscall, here is a snapshot of its stack at this moment:

We just ran into what we think is the same problem.

Note that ext4 fails like this for any 1024 byte sized filesystem (of
zeroes) that you try to mount.  It's really nothing to do with
extended partitions.

Here is a very simple reproducer + stack trace:

  https://bugzilla.redhat.com/show_bug.cgi?id=835019#c4

I will try out the patch suggested later on in this thread.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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