mount rootfs over NFS problem

[kerstin jonsson <kerstin.jonsson@ericsson.com>]

Hi,

I have a powerpc based platform and would like to have access to all the 
latest
RapiodIO patches included in the mm-tree, but I fail to mount my rootfs 
over nfs using the latest mm-kernel.

I can see that the code handling nfs mount in the mm-tree differs 
significantly from the  code in the kernel I used earlier (where nfs 
mount of rootfs works for me - linux-2.6 currently 2.6.36-rc8).

I'm using the same default_config options as input to the mm-build as I 
do for 2.6.36-rc8 and the same kernel cmdline options, the console log 
from the boot show no significant deviation from the two kernels, not 
until I reach the point init init/main.c:kernel_init() where 
/dev/console is supposed to be opened. If it is helpfull in any way, the 
nfs mount attempt fails at:

line 2131 of fs/namespace.c:do_mount()

I guess that there is something that I need to do different to make this 
happen in the mm-tree - possibly something my platform init code should 
have prepared or some extra kernel config option(s) that  is/are needed 
when building the mm kernel.

Please advice!
Kerstin

Kernel command line: root=/dev/nfs rw nfsroot=192.168.0.201:/srv/nfs 
ip=192.168.0.142:192.168.0.201:192.168.0.1:255.255.255.0:unknown:eth0:off console=ttyS0,115200 
riohdid=0 nfsrootdebug

console printout from mm-kernel:
...
IP-Config: Complete:
      device=eth0, addr=192.168.0.142, mask=255.255.255.0, gw=192.168.0.1,
      host=unknown, domain=, nis-domain=(none),
      bootserver=192.168.0.201, rootserver=192.168.0.201, rootpath=
Warning: unable to open an initial console.
Root-NFS: nfsroot=/srv/nfs
VFS: Unable to mount root fs via NFS, trying floppy.
...

console printout from 2.6.36-rc8:

...
IP-Config: Complete:
      device=eth0, addr=192.168.0.142, mask=255.255.255.0, gw=192.168.0.1,
      host=unknown, domain=, nis-domain=(none),
      bootserver=192.168.0.201, rootserver=192.168.0.201, rootpath=
Root-NFS: Mounting /srv/nfs on server 192.168.0.201 as root
Root-NFS:     rsize = 4096, wsize = 4096, timeo = 0, retrans = 0
Root-NFS:     acreg (min,max) = (3,60), acdir (min,max) = (30,60)
Root-NFS:     nfsd port = -1, mountd port = 0, flags = 00000200
Looking up port of RPC 100003/2 on 192.168.0.201
PHY: mdio@fa724520:09 - Link is Up - 100/Full
Root-NFS: Portmapper on server returned 2049 as nfsd port
Looking up port of RPC 100005/1 on 192.168.0.201
Root-NFS: mountd port is 34144
VFS: Mounted root (nfs filesystem) on device 0:12.
...