Re: grub crashes. Crash as in causes the PC to reboot.

[James Courtier-Dutton]

Marco Gerards wrote:
> James Courtier-Dutton <address@hidden> writes:
>
>
> > If by removing it, the geometry command works, I can then look at the
> > real_open_partition function, and add a few grub_printf's to see where
> > it reboots.
> > Does grub have a "grub_pause_for_1_second" function? That would also
> > help by giving me a chance to see what is printed before the reboot.
>
>
> How about a never ending loop like:
>
> for (;;);
>
> --
> Marco
I have now narrowed down the problem a bit. After a lot of reboots!
In file ./grub/stage2/disk_io.c

int next_pc_slice (void)
{
<snip>
if (! rawread (drive, *offset, 0, SECTOR_SIZE, buf)) {
<snip>
}

this is called with drive = 0x81 (which is hd1 the scsi disc), *offset = 0.
It crashes inside the rawread call.

geometry (hd0) sets drive to 0x80 and works.
geometry (hd1) sets drive to 0x81 and crashes!

I conclude that there is some incompatibility between grub and the SCSI 
INT13 BIOS.

I am investigating further.

Cheers
James