Old squashfs partitions does not work in Fedora 11

[Bruno Wolff III]

On Wed, Jul 01, 2009 at 13:15:36 +0200,
  David Björkevik <david at bjorkevik.se> wrote:
> Dear List  [this is my first post]
> 
> In a mixed environment of CentOS 5 and Fedora machines, I use Network
> Block Device to export squashfs-partitions with static archived data
> from a server to client machines. This provides great speed and low load
> on the server.
> 
> When upgrading to Fedora 11, I can no longer access the squashfs
> partitions. I get this message i dmesg:
> 
> SQUASHFS error: Major/Minor mismatch, older Squashfs 3.1 filesystems are
> unsupported
> 
> Is this a bug or a feature? It's quite rare to revoke support for
> filesystems from the kernel... In particular it's a bit weird for
> filesystems generated with Fedora 10 to be unreadable by Fedora 11.
> 
> Should it be posted as a bug? Does anybody know of a workaround? Will I
> have to revert to NFS for sharing the data?

This is probably related to squashfs being upstreamed in kernel 2.6.29.
I assume (but am not 100% sure) that the 4.0 version is what got upstreamed.
Another potential gotcha is that while lzma went into the kernel with 2.6.30,
the ability to use lzma in squashfs didn't. The developer was going to try
to hit the 2.6.31 merge window for this support, but as best I can tell
didn't make it. Though even if he didn't it could still possibly get in.
I am hoping that even if it doesn't make 2.6.31, Fedora considers backporting
the feature so that we get it for F12.