Re: Kernel image size limitations silo?

[jose.marchesi@oracle.com (Jose E. Marchesi)]

Hi John.

    I am in the final process of creating a fresh set of debian-installer
    images for sparc64 and just stumbled over the following comment in
    the scripts which create the sparc install images [1]:
    
    # Sparc64 kernel is so big, that uncompressing it corrupts SILO memory,
    # uncompress it before hand.
    
    Does this apply to the 64-bit version of silo which I built from git
    plus your patches from [2]?

As others already mentioned, Openboot by default allocates 10Mb of
virtual memory for the bootloader.  That leaves from 6 to 8 Mb for the
boot image.  This mainly impacts netbook, because even though silo can
fetch a kernel+initrd image through tftp from a remote server and boot
it, due to the abovementioned limitation this capability does not work
with big boot images.

However, back in 29 Jan 2014 a patch was applied in git silo to
dynamically allocate as much virtual memory as needed using OBT
services:

1e2c4a68b43 SILO/TILO/sun4u: support TFTP booting modern kernels

So you must be fine.

Note that in OLS we don't have that patch backported yet, as we
basically moved to grub2 to support netboot.

On a side note, we had to change tilo in order to support the creation
of big boot images, but that is most definitely fixed upstream as part
of 1e2c4a68b43, so you must be fine.

Salud!