On Mon, 13 Sep 1999 09:58:31 +0900 (JST) 
 nisimura@itc.aist-nara.ac.jp (Toru Nishimura) wrote:

 > NCR53C94-2 TCDS (used in high end DEC3000) has been suffered from
 > timing parameter related trasnfer problems for long time.

Yah, Michael Hitch has fixed this... I imagine he'll commit these
soon.

 > I'm experiencing panics at bus_dmamap_load() inside tcds_dma_setup()
 > when used with DECstation.  I remembered that once the driver was
 > usable enough to run iozone, however recently disklabel(8) immediately
 > blows away kernel all the time.

Can you send me a baktrace?  The TCDS driver hasn't changed recently....

        -- Jason R. Thorpe <thorpej@nas.nasa.gov>