dma-pool fixes

[David Rientjes]

On Fri, 31 Jul 2020, Christoph Hellwig wrote:

> > Hi Nicolas, Christoph,
> > 
> > Just out of curiosity, I'm wondering if we can restore the earlier
> > behaviour and make DMA atomic allocation configured thru platform
> > specific device tree instead?
> > 
> > Or if you can allow a more hackish approach to restore the earlier
> > logic, using of_machine_is_compatible() just for my device for the
> > time being. Meanwhile I'm checking with other developers running the
> > mainline kernel on sdm845 phones like OnePlus 6/6T, if they see this
> > issue too.
> 
> If we don't find a fix for your platform I'm going to send Linus a
> last minute revert this weekend, to stick to the no regressions policy.
> I still hope we can fix the issue for real.
> 

What would be the scope of this potential revert?