Re: [PATCH 00/35] Add HMM-based SVM memory manager to KFD

On Wed, Jan 06, 2021 at 10:00:52PM -0500, Felix Kuehling wrote:

This is the first version of our HMM based shared virtual memory manager for KFD. There are still a number of known issues that we're working through (see below). This will likely lead to some pretty significant changes in MMU notifier handling and locking on the migration code paths. So don't get hung up on those details yet.

[...]

Known issues:

• won't work with IOMMU enabled, we need to dma_map all pages properly
• still working on some race conditions and random bugs
• performance is not great yet

What would those changes looks like ? Seeing the issue below i do not see how they inter-play with mmu notifier. Can you elaborate.

Cheers, Jérôme