NFS panic

[Sascha Wildner]

Matthew Dillon wrote:

:PROBLEM 1
:---------
:When I set nfs_server_enable to "yes" on one of my test machines and 
:export a few directories (which reside on FAT32 partitions) I get 
:reproducable panics on that machine as soon as I try to write from 
:another machine. Reading seems to work.
:
:I've taken the following picture: http://yoyodyne.ath.cx/tmp/LPIC0019.JPG
:
:The top line reads: "panic: lockmgr: locking against myself"
:
:I would have liked to provide a crash dump and everything but 
:unfortunately...

    The problem is virtually guarenteed to be msdosfs not playing nice
    with the NFS server.  Probably a bug in the msdosfs lookup code not
    releasing a vnode lock that it should be releasing.  I will try to 
    recreate it after christmas.

    I'm assuming that an NFS export of a UFS filesystem works fine?
Yes, UFS works fine.


:PROBLEM 2
:---------
:For some strange reason I can't produce crash dumps on that box.
:
:Here's what happens:
:
:db> call dumpsys
:
:dumping to dev #ad/0x20041, offset 2097536
:dump ata4: resetting devices .. done
:1023
:
:And then the machine just sits there.
:
:Sascha
    Don't know about that one.  hmm.  Maybe its deadlocked on a vnode,
    try setting sysctl kern.sync_on_panic to 0.
No, that didn't help.

Sascha