Bug#239111: Not fixed when I tested it

[Robert Millan]

On Sat, Aug 14, 2004 at 11:22:45PM -0300, Joey Hess wrote:
> Robert Millan wrote:
> > I still don't understand why the current solution doesn't work.  xfs_freeze
> > suposedly puts the filesystem in a state that all write requests are blocked.
> > 
> > Am I missing something?
> 
> xfs_freeze is definitly causing all write to block. Apparently something
> in grub-installer must then be doing a write while the filesystem is
> frozen. I don't know for sure what it is; I suspect it may be more than
> one thing. One place that seems likely to write and block is the
> redirection of $grub_shell to $log_file. Since removing that one doesn't
> fix it, I'm left assuming that running $grub_shell itself somehow causes
> a write, and thus a freeze. Maybe getting strace on there and stracing
> it would help.

The grub shell needs to write to /dev/hda for grabbing stage files into the
boot sector (see lib/device.c in grub source code).

Maybe what we want is to hack grub so that is freezes the filesystem only when
it's time to, instead of reliing on grub-install to do that.  However, this
calls for a C interface that is equivalent to xfs_freeze.  Is there a library
or something?

-- 
Robert Millan

(Debra and Ian) (Gnu's Not (UNiplexed Information and Computing System))/\
(kernel of *(Berkeley Software Distribution))