[RFC] mm/hmm: pass mmu_notifier_range to sync_cpu_device_pagetables

[Jason Gunthorpe]

On Wed, Jul 03, 2019 at 12:49:12AM +0200, Christoph Hellwig wrote:
> On Tue, Jul 02, 2019 at 07:53:23PM +0000, Jason Gunthorpe wrote:
> > > I'm sending this out now since we are updating many of the HMM APIs
> > > and I think it will be useful.
> > 
> > This make so much sense, I'd like to apply this in hmm.git, is there
> > any objection?
> 
> As this creates a somewhat hairy conflict for amdgpu, wouldn't it be
> a better idea to wait a bit and apply it first thing for next merge
> window?

My thinking is that AMD GPU already has a monster conflict from this:

 int hmm_range_register(struct hmm_range *range,
-                      struct mm_struct *mm,
+                      struct hmm_mirror *mirror,
                       unsigned long start,
                       unsigned long end,
                       unsigned page_shift);

So, depending on how that is resolved we might want to do both API
changes at once.

Or we may have to revert the above change at this late date.

Waiting for AMDGPU team to discuss what process they want to use.

Jason