Re: Reader / writer lock error: rw_vector_exit: assertion failed: RW_COUNT(rw) != 0

[Sarton O'Brien <bsd-xen%roguewrt.org@localhost>]

Hi Reinoud,

On Tue, 15 Jul 2008 10:44:48 pm Reinoud Zandijk wrote:
> I kind of replicated it; if i move the dir *inside* the exported fs i get a 
> pwd on the _client_ stuck in [tstile] :-S This alone is pretty serious.

Eww ... I'll have to watch that one.

> But if i move the dir *outside* the exported fs i get:
> 
> client:
> ------
> luiaard# mkdir 1
> luiaard# cd 1
> luiaard# mkdir 2
> luiaard# cd 2
> luiaard# ls -al
> total 2
> drwxr-xr-x  2 root  wheel  512 Jul 15 14:33 .
> drwxr-xr-x  3 root  wheel  512 Jul 15 14:33 ..
> luiaard# pwd
> /root/1/2
> 
> 
> server:
> ------
> heethoofdje# pwd
> /usr/exports/luiaard/root/1
> heethoofdje# mv 2 ~
> 
> 
> client
> -----
> luiaard# cd ..
> luiaard# ls -al
> <list of ~>
> luiaard# pwd
> Reader / writer lock error: rw_vector_exit: assertion filed : RW_COUNT(rw) 
> != 0
> lock address : 0x00000000c7267ab4
> current cpu  :                  0
> current lwp  : 0x00000000c70080a0
> owner/count  : 000000000000000000 flags    : 000000000000000000
> panic: lock error
> 
> 
> XXX note that the ls -al on `luiaard' (the client) should list ~/1 but 
> lists ~ !!! and thus most likely unlocks/locks the wrong lock and BOEM!

Yep, that's the same thing I'm seeing.

Also, when I stumbled on the above, I don't know how an NFS sever/client is 
meant to react when an export dir is moved or deleted but when it's happened, 
I've yet to find a way of unmounting/remounting without rebooting the client. 
umount won't recognise the stale mount at all.

Sarton