Re: msk(4) require to sync status buffer

[Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>]

dyoung%pobox.com@localhost wrote:

> IMO, the bus back-end should KASSERT or panic when a driver may lose data
> by calling bus_dmamap_sync() on a region that is either non-cacheline
> aligned, or smaller than a cacheline.  We will soon detect and squash
> the bugs as broken drivers panic the kernel.

Hmm, it might be a good idea, but I don't think bus_dma(9)
backend can see if DMA is already started or not.
Writeback before DMA is a valid op, and we can't do
invalidate against unaligned buffer in any case.
---
Izumi Tsutsui