Bug#541273: grub-pc: vga= kernel command line option has no effect when grub runs in console mode

[Johannes Stezenbach]

I was using a somewhat non-standard vga=0x376 (AMD RS780 chipset graphics),
which is not supported by grub2 (grub2 apparently uses a hardcoded list
of vesa modes for vga= parsing which have nothing to do with the mode which
the VESA BIOS actually supports).

To get it working I needed:

- insmod vbe
- set gfxpayload=1600x1200x32
- remove the vga= from the linux command line
  (grub2 overrides gfxpayload when vga= is set)

I'd suggest that if GRUB_TERMINAL=console in /etc/default/grub,
then GRUB_GFXMODE is used to set gfxpayload instead of gfxmode.
And do "insmod vbe" if GRUB_GFXMODE is set even for GRUB_TERMINAL=console.
Plus add some helpful comments about this to /etc/default/grub.

PS: I tried GRUB_GFXMODE=1600x1200x32 without GRUB_TERMINAL=console,
but grub2 then just appears in a small rectangle in the upper left
corner of the screen.  I'd prefer text mode for grub, but if graphics
mode would work in a useful way I'd just use that.


Thanks
Johannes