Re: [PATCH] asm-generic: add dma-mapping-linear.h

Arnd Bergmann
2009-06-01T11:42:28Z

On Monday 01 June 2009, Russell King wrote:

> I didn't say "for all architectures". I said that the end conditions
> need to be the same no matter how DMA is done.
>
> And yes, it does matter with some cache types. VIPT aliasing caches
> and VIVT caches both need to ensure that condition is met, otherwise
> userspace doesn't see the data.

Ok, thanks for the explanation.

> While we can hand-wave and say "some other part of the code should
> handle this" I've had that disucssion several times, and that's where
> this requirement eventually was stated. And, really, I'm not going
> to re-discuss it yet again - I really don't have time or motivation
> at present to be involved in yet another hand-waving egotistical
> debate over it.

I was not trying to start a debate over this, just being curious.