Re: netbsd-5 panic in NFS

[Chris Ross <cross+netbsd%distal.com@localhost>]

  I think a key point here may be that I mounted a local FFS  
directory over an NFS directory, but not *directly*.  This may've been  
driver error, or it may be a bug in the union FS, but.

  I had:

  nfsserver:/data/NetBSD                        /data/NetBSD
  /dev/sd0a                                     /local
  <above>:/local                          /data

  This seems not to work quite right.  I'm not sure, is this supposed  
to work?  Should accesses in /data/foo just be through to /local/foo,  
and access to /data/NetBSD work through to the backing NFS store, but  
write to /local/NetBSD?

  Anyway.  Just more information.  I'm still having some problems  
getting the union mounts to work the way I expect.  Sometimes the  
ownerships show up right, sometimes not.  Haven't worked that out yet.

                        - Chris

On Nov 30, 2008, at 13:02, Chris Ross wrote:
>  I have a dual-UltraSPARC machine (sbus) running a netbsd-5 branch  
> kernel and userland as of today/yesterday.  I am 99% sure that I was  
> able to run things alright with just the NFS root and swap, and I  
> think I even managed to NFS mount NetBSD sources (from the same NFS  
> server), and then union-mount a local disk over it.  All of this  
> allowed me to do a "df" and see the result.
>
>  However, now twice in a row, I've gotten the following panic:
>
> # df
> trap type 0x34: cpu 0, pc=12ab8e4 npc=120ec10 pstate=44820006<PRIV,IE>
> kernel trap 34: mem address not aligned
> Stopped in pid 572.1 (df) at    netbsd:kauth_cred_ngroups+0x4:   
> ld              [%o0 + 0x58], %o0
> db{0}> bt
> nfs_getattr(bcef418, 8, 164d8e8, 0, 0, 1) at netbsd:nfs_getattr+0x12c
> VOP_GETATTR(c9d75b0, bcef5d0, fffffffffffffffe, b7633a4, 0, 1) at  
> netbsd:VOP_GETATTR+0x3c
> union_allocvp(1, d340000, 0, 0, 20000, c9363a0) at  
> netbsd:union_allocvp+0xec
> union_lookup(0, 9, 9, 10, 200, 0) at netbsd:union_lookup+0x280
> VOP_LOOKUP(c936ac0, bcefbe0, bcefc08, 0, 0, 0) at netbsd:VOP_LOOKUP 
> +0x3c
> lookup(bcefbb8, bcef9c8, 20, 0, 0, 0) at netbsd:lookup+0x33c
> namei(0, 2650bc0, bcefc08, bcefbb8, 0, 0) at netbsd:namei+0x108
> do_sys_pstatvfs(b7633a0, 4080326c, 1, d340970, 0, 0) at  
> netbsd:do_sys_pstatvfs+0x20
> sys_statvfs1(b7633a0, bcefdc0, bcefe00, 1, 202cc0, 1818c50) at  
> netbsd:sys_statvfs1+0x20
> syscall_plain(bcefed0, 6, 4053da9c, 4053daa0, 0, bcefdc0) at  
> netbsd:syscall_plain+0x134
> ?(4080326c, 408031a0, 1, 3, fffffffffffffffa, 40803a40) at 0x1008c68
>
>  Anyone have any idea what this is, or how to fix it?  Thanks...   
> I'm going to back off to making the mounts one at a time by hand to  
> see what I can get working.
>
>                  - Chris