Re: Making port-alpha usable again

[Tobias Nygren <tnn%NetBSD.org@localhost>]

On Sun, 30 Jul 2017 12:42:53 +0200
Martin Husemann <martin%duskware.de@localhost> wrote:

> On Sat, Jul 29, 2017 at 04:37:40PM +0200, Tobias Nygren wrote:
> > I found that for the network cards, the problem goes away if I sprinkle
> > a memory barrier before bus_dmamap_load. (See attached patch.)
> 
> This should happen in the bus_dmamap_sync() function. If a driver does
> not call that properly, the driver is buggy.

Yes, and it does, but for some reason it is not sufficient. It's
not an MI problem. It seems like tsunami core logic is the common
denominator here.