Kernel and ADM hardware roulette ( was AMD graphics performance regression in 4.15 and later )

[Christian König]

Am 08.06.2018 um 08:02 schrieb Christoph Hellwig:
> On Thu, Jun 07, 2018 at 02:32:46PM +0200, Gabriel C wrote:
>> Ok done.. bisect points to:
> What is the failure mode you are seeing?  Can't find anything in the
> mail unfortunately.

As far as I analyzed it we now get an -ENOMEM from dma_alloc_attrs() in 
drivers/gpu/drm/ttm/ttm_page_alloc_dma.c when IOMMU is enabled.

Still need to figure out which parameters we want to use for the 
allocation, but I think it is only 4k or 8k.

Regards,
Christian.