Re: boot failed with gzip'ed modules

On Friday 25 April 2008 05:20:34 pm David Naylor wrote:
> Hi,
>
> I have a live CD that has a GENERIC kernel and that loads some modules
> before booting.  They have been gzip'ed to save space however suddenly the
> booting has stopped.   The kernel loads and then after the first line of
> the modules to load it stops:

I've seen reports of problems with gzip'd modules on 7.0.  You'll probably 
have to add debugging or look at the diffs between 6.3 and 7.0 of the boot 
code (sys/boot and lib/libstand) to narrow down things to try.  (For example, 
did moving malloc up above 1MB break it somehow.)

> Oh, on an aside.  What is the BTX and why is the bootloader i386 even for
> an amd64 system (I suspect it is because there is no need for an amd64
> bootloader [unless kernels and modules suddenly exceed 4GB 8-/ ])?

1) BTX is a mini-kernel that the boot code uses.  This lets us write the boot
   loader as a 32-bit app in C rather than assembly.
2) Yes, the amd64 code uses the i386 bootstrap.  amd64 CPUs start up in real
   mode just like i386 and you can't easily call the BIOS from long mode
   anyway, so a different bootstrap for amd64 would be rather gratuitous.

-- 
John Baldwin