KB9202 booting large kernels

[M. Warner Losh]

In message: <20060617004355.GA99313 at mail.secure.net>
            David Sharp <daimon at dev-random.org> writes:
: i have been succesful with smaller nfs-root kernels booting on the
: KB9202.  however, when i try larger MD_ROOT kernels it does not work.  the
: break point is around 2.6MB total kernel size.  as the size approaches 
: that number there will be some error messages about elf linker not finding a
: symbol, or no error and just garbage on the console.  after passing the 2.6M
: mark by more than 10kB it silently hangs.
: 
: does anyone have an idea what might be going wrong?

Yes.

There's multiple problems.

First, we weren't allocating enough stack, so we overflowed the stack.

Next, there's not PTEs allocated for a kernel that's so large.

Finally, the default boot loader from kwikbytes is lame.

All the problems have been corrected in p4.  I've not had the time to
merge them back into the mainline code.

Warner