Re: [Xen-devel] pvgrub2 is merged

[Andrey Borzenkov <arvidjaar@gmail.com>]

В Wed, 27 Nov 2013 17:24:53 +0100
Fabio Fantoni <fabio.fantoni@m2r.biz> пишет:

> Il 27/11/2013 17:03, Vladimir 'φ-coder/phcoder' Serbinenko ha scritto:
> > On 27.11.2013 16:59, Fabio Fantoni wrote:
> >> Il 27/11/2013 12:50, Vladimir 'φ-coder/phcoder' Serbinenko ha scritto:

> >>> That pretty much explains what happened: you don't have any
> >>> /boot/grub2/grub.cfg and when looking for /boot/grub/grub.cfg GRUB found
> >>> its own memdisk and fell into recursion. I'm not sure what should be the
> >>> proper way to solve this recursion.

Yes, it was a bit naive on my side. Recursion in principle can be
stopped by using global variable, but search is limited to the first
match only anyway, so I guess it is not worth it.

> >>
> >> Anyone know how to exclude memdisk from the search please?
>

Please look in grub2 sources at docs/osdetect.cfg. It implements
advanced run-time detection of possible bootable files from
various operating systems. It boils down to loop across all devices,
and of course you can either limit device names (like looking for hd*
only) or explicitly exclude known ones (like memdisk).

> Is it possible to specify a different default grub.cfg path (different 
> from all other distributions) changing this command:
> ./grub-mkstandalone --grub-mkimage=./grub-mkimage -o pvgrub2.xen -O 
> x86_64-xen -d grub-core/ boot/grub/grub.cfg
> Is it hardcoded as /boot/grub/grub.cfg for grub memdisk or can be set?
>

Not really. Currently the situation is

- grub-mkstandalone hardcodes $prefix as (memdisk)/boot/grub
- after launch grub unconditionally starts "normal" module if at all
  possible
- normal module always tries to load and execute $prefix/grub.cfg if no
  explicit configuration file name is given as argument

But I think that using osdetect.cfg or something based on this idea
won't require changing defaults at all.