hi jukka,

this is a known problem.  NFS doesn't do vnode locking, but with UBC
all filesystems are required to do vnode locking, at least for
VOP_READ() and VOP_WRITE() (ie. the VOPs which use ubc_alloc()).

-Chuck


On Thu, Feb 01, 2001 at 08:42:51AM +0200, Jukka Marin wrote:
> Under 1.5Q:
> 
> panic: ubc_fault: concurrent writes vp 0xd3e4aef4
> 
> Is this a known problem or should I examine the core file somehow?
> 
>   -jm