I was pointed out that it might be of interest.

I found that nfs_namei uses not completly(not enought) initialized
nameidata for it's lookup which definitely causes a problem seen as
.==.. over nfs. The patch below eliminates that problem but in the
same time it's not optimal. Under the most suspiction is ni_rootdir field
but I havn't got enought time so far to investigate it further.

	Andrey

Index: nfs_serv.c
===================================================================
RCS file: /cvsroot/syssrc/sys/nfs/nfs_serv.c,v
retrieving revision 1.60
diff -r1.60 nfs_serv.c
370a371,372
> 	memset(&nd, 0, sizeof(nd));
> 
1308a1311,1312
> 	memset(&nd, 0, sizeof(nd));
> 
1533a1538,1539
> 	memset(&nd, 0, sizeof(nd));
> 
1689a1696,1697
> 	memset(&nd, 0, sizeof(nd));
> 
1776a1785,1787
> 	memset(&fromnd, 0, sizeof(fromnd));
> 	memset(&tond, 0, sizeof(tond));
> 
1977a1989,1990
> 	memset(&nd, 0, sizeof(nd));
> 
2077a2091,2092
> 	memset(&nd, 0, sizeof(nd));
> 
2213a2229,2230
> 	memset(&nd, 0, sizeof(nd));
> 
2325a2343,2344
> 
> 	memset(&nd, 0, sizeof(nd));