Re: [Etherboot-developers] NetBSD ELF/a.out support

[Doug A. <amb...@am...>]

Wojciech Puchar writes:
| i just managed to boot NetBSD with etherboot's FreeBSD loader.
| 
| the only problem is
| 
| a) NetBSD has different boot parameters than FreeBSD. i hardwired
| REALBASEMEM and REALEXTMEM to kernel so it's able to get memory and runs
| well, except it doesn't know what was boot device and boot file name
| (no bootinfo at all)
| 
| b) I am able to write NetBSD support to etherboot except there's no method
| of detecting if kernel is NetBSD or FreeBSD (at least i don't know) other
| than scanning memory for "The NetBSD Foundation, Inc.  All rights
| reserved." which seems quite stupid.

There seems to be some info in to find a FreeBSD header via:
#ifdef ELFCORE
size_t  prpsoffsets32[] = {
        8,              /* FreeBSD */
        28,             /* Linux 2.0.36 */
        32,             /* Linux (I forget which kernel version) */
        84,             /* SunOS 5.x */
};

and then I see this comment 
/*
 * Look through the program headers of an executable image, searching
 * for a PT_NOTE section of type NT_PRPSINFO, with a name "CORE" or
 * "FreeBSD"; if one is found, try looking in various places in its
 * contents for a 16-character string containing only printable
 * characters - if found, that string should be the name of the program
 * that dropped core.  Note: right after that 16-character string is,
 * at least in SunOS 5.x (and possibly other SVR4-flavored systems) and
 * Linux, a longer string (80 characters, in 5.x, probably other
 * SVR4-flavored systems, and Linux) containing the start of the
 * command line for that program.

So I'd use that type of scheme.  It in the common source for "file" from
Christos Zoulas.

I can try out any patches you have and verify it doesn't break FreeBSD
or put a sample FreeBSD kernel on my web-site for you to test.

Doug A.