Re: [PATCH 06/10] swiotlb: use swiotlb_map_page in swiotlb_map_sg_attrs

From: Christoph Hellwig
Date: Fri Nov 09 2018 - 02:50:00 EST


On Tue, Nov 06, 2018 at 05:27:14PM -0800, John Stultz wrote:
> But at that point if I just re-apply "swiotlb: use swiotlb_map_page in
> swiotlb_map_sg_attrs", I reproduce the hangs.
>
> Any suggestions for how to further debug what might be going wrong
> would be appreciated!

Very odd. In the end map_sg and map_page are defined to do the same
things to start with. The only real issue we had in this area was:

"[PATCH v2] of/device: Really only set bus DMA mask when appropriate"

so with current mainline + that you still see a problem, and if you
rever the commit we are replying to it still goes away?