Hi,

according to bus_dma(9), the third (alignment) and fourth
(boundary) parameters of bus_dmamem_alloc() must be a
power of 2. Grepping for bus_dmamem_alloc in src/sys/dev/*/*.c
shows many calls where one of the two parameters is 0, i.e.
not a power of 2. One of the many examples is ic/cs4231.c 1.2,
line 249.

While an alignment of 0 is probably harmless ("it will be
rounded up to the hardware page size"), a boundary of 0 is
not (bus_dma(9): "A boundary value less than the size of the
allocation is invalid.").

How is the value 0 handled?

    Ingolf
-- 

Ingolf Koch     ICQ#60829470     Beste Kneipe in Jena-Ost
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