Re: [patch] grub incorrectly identifies ext3 as fat

[Robert Millan <rmh@aybabtu.com>]

On Thu, Oct 29, 2009 at 02:58:09PM +0000, Andrew Clausen wrote:
> Hi all,
> 
> grub (both the boot loader, and grub-probe) incorrectly identifies my
> ext3 partition as containing a fat file system. This means it can't
> boot without manual tweaking.  The problem is caused by stale fat
> signatures... this is probably a common problem, as mke2fs often
> doesn't wipe old signatures.
> 
> I wrote a patch.  In order for a file system to be considered
> detected, dir() must not only succeed, it also must find at least one
> file or directory. This is pretty effective at ruling out misdetecting
> a filesystem based on a stale signature that wasn't wiped by mkfs.

We already had code for this, see:

2009-09-05  Robert Millan  <rmh.grub@aybabtu.com>

        * util/grub-probe.c (probe): Comment out buggy codepath, which  
        was unexpectedly enabled by Colin Watson's 2009-09-02 fix.  This
        should be re-enabled after 1.97.

> This shouldn't have any collateral damage, because empty file systems
> are useless to Grub.

Unlike the filesystem driver, grub-probe already knows we want to probe for
a file.  Then this assumption won't be necessary.

-- 
Robert Millan

  The DRM opt-in fallacy: "Your data belongs to us. We will decide when (and
  how) you may access your data; but nobody's threatening your freedom: we
  still allow you to remove your data and not access it at all."