Bug#442382: Updated multipath patch for grub-legacy

[Robert Millan]

reassign 442382 grub-common
thanks

On Sun, Feb 01, 2009 at 12:22:45PM +0100, Guido Günther wrote:
> On Sat, Jan 31, 2009 at 09:16:27PM +0100, Robert Millan wrote:
> > tags 442382 - patch
> > thanks
> > 
> > On Thu, Jan 29, 2009 at 04:27:54PM +0100, Guido Günther wrote:
> > > +--- a/lib/device.c.org	2009-01-29 13:31:54.000000000 +0100
> > > ++++ b/lib/device.c	2009-01-29 13:38:48.000000000 +0100
> > 
> > This is not the right place.  We use grub-mkdevicemap for all new device types,
> > please modify that instead.
> Please read the patch carefully. I know that we use grub-mkdevicemap for
> device map generation. The important part of the patch is the last hunk.
> Independent of the probing (which we currently don't need in d-i, since
> we use the workaround dmraid uses) we need to pick the right *partition*

Sorry, I forgot about partition selection.  Both things are handled separately,
and both of them might need to be adjusted.

But this is not the right place for that either.  grub-install determines
partitions with:

        GRUB_LEGACY_0_BASED_PARTITIONS=1 grub-probe --device-map=${device_map} -t drive -d "$1"

and update-grub determines partitions with:

        GRUB_LEGACY_0_BASED_PARTITIONS=1 grub-probe --device-map=${device_map} -t drive -d "$1" 2> /dev/null || {

In both cases, it's grub-probe you want to fix.  There are other code paths,
but they're not essential, and we're not currently supporting them.

Note: grub-probe uses a generic heuristic that works for most device paths,
it's possible that no change is needed there.

-- 
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."