port-i386/47566: kernel ignores root device parameter specified in boot loader

[Takahiro HAYASHI <t-hash%abox3.so-net.ne.jp@localhost>]

>Number:         47566
>Category:       port-i386
>Synopsis:       kernel ignores root device parameter specified in boot loader
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-i386-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Feb 14 12:30:00 +0000 2013
>Originator:     Takahiro HAYASHI
>Release:        NetBSD 6.99.16 (201301271040Z from nyftp)
>Organization:
>Environment:
System: NetBSD  6.99.16 NetBSD 6.99.16 (MONOLITHIC) #0: Sun Jan 27 17:20:26 UTC 
2013  
builds%b6.netbsd.org@localhost:/home/builds/ab/HEAD/i386/201301271040Z-obj/home/builds/ab/HEAD/src/sys/arch/i386/compile/MONOLITHIC
 amd64
Architecture: x86_64
Machine: amd64
>Description:
        Recent kernel ignores root device parameter specified in
        boot loader and always boots from hdXa.

        I installed NetBSD/amd64 on wd0a and NetBSD/i386 on wd0f.
        (This pc has one disk, so hd0 is wd0.)
        They are in same MBR partition.  I don't use any dkwedges.
        /boot.cfg on wd0a has following lines:

menu=nbamd64 (hd0a):dev hd0a:;rndseed /var/db/entropy-file;boot
menu=nbi386 (hd0f):dev hd0f:;rndseed /var/db/entropy-file;boot
default=1

        When I choose second line to boot i386, the boot loader loads
        the kenrel from wd0f:/netbsd but the kernel sets the root to wd0a
        because it tries to read 64-bit version of /sbin/init from wd0a
        and complain about it (ENOEXEC), finally stops with error.

11989372+553852+472252 [601344+592200]=0xd8f570
Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
    2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013
    The NetBSD Foundation, Inc.  All rights reserved.
Copyright (c) 1982, 1986, 1989, 1991, 1993
    The Regents of the University of California.  All rights reserved.

NetBSD 6.99.16 (MONOLITHIC) #0: Sun Jan 27 17:20:26 UTC 2013
        
builds%b6.netbsd.org@localhost:/home/builds/ab/HEAD/i386/201301271040Z-obj/home/builds/ab/HEAD/src/sys/arch/i386/compile/MONOLITHIC
total memory = 3068 MB
avail memory = 3004 MB
[...snip...]
boot device: wd0
root on wd0a dumps on wd0b
root file system type: ffs
exec /sbin/init: error 8
init: trying /sbin/oinit
exec /sbin/oinit: error 2
init: trying /sbin/init.bak
exec /sbin/init.bak: error 2
init path (default /sbin/init):

>How-To-Repeat:
        1) Carve up a BSD partition other than wd0a, assuming wd0f.
        2) Put kernel on wd0f.
        3) Boot kernel from boot loader by typing "dev hd0f:" and "boot"
>Fix:
        No idea.

--
t-hash