Re: [BISECTED REGRESSION] b43legacy broken on G4 PowerBook

From: Christoph Hellwig
Date: Tue Jun 11 2019 - 03:59:35 EST

On Tue, Jun 11, 2019 at 04:59:54PM +1000, Benjamin Herrenschmidt wrote:
> Ah stupid me ... it's dma_set_mask that failed, since it has no idea
> that the calling driver is limited to lowmem.
> That's also why the "wrong" patch worked.
> So yes, a ZONE_DMA at 30-bits will work, though it's somewhat overkill.

Well, according to Larry it doesn't actually work, which is odd.