Synopsis: bus_dmamap_load_mbuf may create zero length DMA segments

Responsible-Changed-From-To: kern-bug-people->thorpej
Responsible-Changed-By: thorpej@netbsd.org
Responsible-Changed-When: Thu, 25 Nov 2004 16:32:55 +0000
Responsible-Changed-Why:
I will handle this PR, and change all of the bus_dma back-ends.


State-Changed-From-To: open->analyzed
State-Changed-By: thorpej@netbsd.org
State-Changed-When: Thu, 25 Nov 2004 16:32:55 +0000
State-Changed-Why:
This is really the correct patch, but I want to add some instrumentation
so we can really know how much this happens.