[armedslack] GRUB 2 patch

[Alan Hourihane]

Hello All,

Here's the verified fix for grub booting problems on a RiscPC that has
256MB of RAM.

The asm.S fix is something I found out from NetBSD's boot scripts and
they also workaround it in a similar way. It seems RiscOS 4.x (i'm not
sure on which versions) overrun when writing the page table arrangement
and allocating this extra memory makes it work. I guess I could test
further on what values make sense, but it's only another 128kb, so I'm
not worried here. This problem usually causes grub to crash with a
backtrace or possibly a data abort.

The misc.c fix is because page 65536 is actually valid. And for a RiscPC
with 256MB of RAM it's the only page that details the layout. So without
knowing about it, we get "out of memory" errors from GRUB.

Both these fixes have been verified and work for me.

I've BCC'ed Tim to this too, rather than expose his email address on the
mailing list.

Many thanks to Tim for supporting GRUB on RiscOS in the first place.

Alan.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: grub.patch
Type: text/x-patch
Size: 1006 bytes
Desc: not available
URL: <http://lists.armedslack.org/pipermail/armedslack/attachments/20070413/1d848515/attachment.bin>