Configuring kernel with multidisk swap

[Per Bojsen <pb%delta.dk@localhost>]

I've been trying to configure a new kernel that allows me to swap on
more than one disk, but has not been successful so far.  Here's what
I've done:

1) I started by changing the `config netbsd swap on generic' line to
`config netbsd swap on sd2b sd1b' (sd2 is my main NetBSD disk, and
where my root partition and swap partition is; sd1 is the disk I want
to swap to besides sd2), but config reported syntax error on the
config line.  Hmm.

2) I checked the NetBSD mail archives and it didn't reveal the syntax
error.  I then checked the config source and found out that you have
to add an `and' between the swap partitions.  So I changed the config
line to: `config netbsd swap on sd2b and sd1b'.  Now config reported
`no root disk specified'.

3) Ok, I then added a root specification and a dumps specification,
also, just for completeness, so the config line was changed to:
`config netbsd root on sd2a swap on sd2b and sd1b dumps on sd2b'.
This allowed config to run successfully.  I did `make depend', and
compiled the kernel, but the final link failed with `undefined symbol
_setconf referenced from autoconf.o'.

4) I checked autoconf.c and found that when GENERIC is #define'd the
setconf() function is called.  This function is defined in
swapgeneric.c which is included in the kernel build when using `swap
on generic'.  But when you're not using that, config produces a
swapnetbsd.c source file, which does not include setconf().  Ok, I
removed `options GENERIC' from the configuration and re-config'd and
recompiled, and finally the build succeeded.

But when I rebooted using the new kernel the boot failed with `exec
/sbin/init error 12' and `panic: no init'.  This sounds like the wrong
partition was selected as root.  Hmm.  I'm positive sd2a is my root
partition when running my normal kernel (the one with `swap on
generic').  Does the removal of the GENERIC option and/or the change
of root/swap/dumps options change the way disk devices are named?  

I also tried `config netbsd root on sd2 swap on sd2 and sd1 dumps on
sd2' with the same result.  And I tried to `make clean' before
recompiling with the same result.  Is there something obvious I'm
missing?  The kernel configuration is basically GENERIC with
unnecessary options removed (device drivers for non-existent hardware,
for instance).

-- 
Per Bojsen                                   Email: pb%delta.dk@localhost
DELTA IC Design                                     
bojsen%moria.home.id.dtu.dk@localhost
Venlighedsvej 4, Hoersholm, Denmark