Back to Basics

Rodrigo Ventura yoda@isr.ist.utl.pt
Fri, 20 Mar 1998 15:28:30 +0100 (GMT+0100)


        For a second I imagined myself using the dreamed LispOS (with
some help of an now off-line Explorer Lisp machine on the corner of my
eye) and wondering whether we are trying to reinvent the weel. I mean,
let's imagine we are experimenting with LispOS code. Would we need to
reboot the machine in order to try something out? Do we really want a
LispOS that takes control over the whole machine? Wouldn't it be
better to boot LispOS ontop Linux. And in the initial development
stages, LispOS could be booted while Linux was running.

This idea is not new, and it was discussed before in this mailing
list. I think that it would be much better to work out LispOS directly
ontop the Linux kernel, ie no libc, no init, no nothing. We could use
Linux kernel _directly_ (which would be great since it is under
high-speed development). Only that instead of running /sbin/init, our
LispVM could be launched. Or better yet, maintain the old init (I
suppose it comes from the kernel sources, right?), and configure the
rest via /etc/inittab. A minimal binary tree of ELF executables is
needed, the a.out support can be stripped out from the kernel, and
once the LispVM (including the JIT compiler) has been launched, all
other stuff is in LispOS bytecode.

I don't have much OS code expertise, but these ideas make me
entusiastic enough to think about some little experimentation to build
a ultra-minimal LispOS bootstrap. And all of these without thinking
about boot loaders, assembly bootstrap, serial debugging, etc...

        Regards,

--

*** Rodrigo Martins de Matos Ventura, alias <Yoda>
***  yoda@isr.ist.utl.pt, http://www.isr.ist.utl.pt/~yoda
***   Instituto de Sistemas e Robotica, Polo de Lisboa
***    Instituto Superior Tecnico, Lisboa, Portugal
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