Re: GRUB "embed" function for stage1.5 broken??

[Jochen Hoenicke]

On Nov 9, address@hidden wrote:
> 
> In putting in some extra consistency checks for the GRUB shell
> installer (and for Linux adding BMAP functionality for the stage2),
> I seem to have come across an issue...
> 
> The "setup" builtin function will try to install a stage 1.5, but
> then overwrite it immediately with a stage2.

First setup doesn't access the drive directly but just calls embed and
install which do the real work.  The setup command checks if a
stage1.5 is there and if it can be embedded in a safe place.  If that
succeeds it calls install with all required parameters.

Note that the install command with an embedded stage1_5 takes several
parameters: STAGE2 is actually the location where stage1_5 was
embedded, CONFIG_FILE is the location of stage2 (the logic is that
stage2 is the config file for stage1_5).  REAL_CONFIG_FILE is the
location of menu.lst.  The naming of the parameters is a bit
misleading.

The "install" command doesn't generate a sector bitmap for stage2, the
CONFIG_FILE parameter.  But it needs to write the string CONFIG_FILE
and REAL_CONFIG_FILE (this aren't block bitmaps, but plain file names)
to the embedded stage1_5 resp. the stage2.  The stage2 is on the
filesystem, therefore there is the --stage2=... command to make that
write more safe.

  Jochen