[PATCH v1 0/3] udmabuf: Add support for page migration out of movable zone or CMA

[Kasireddy, Vivek]

Hi Jason, David,

> 
> > Sure, we can simply always fail when we detect ZONE_MOVABLE or
> MIGRATE_CMA.
> > Maybe that keeps at least some use cases working.
> 
> That seems fairly reasonable
AFAICS, failing udmabuf_create() if we detect one or more pages are in
ZONE_MOVABLE or MIGRATE_CMA would not be a recoverable failure --
as it would result in the failure of Guest GUI (or compositor).

I think it makes sense to have a generic version of 
And, since check_and_migrate_movable_pages() is GUP-specific, would
it be ok to create a generic version of that (in mm/migrate.c) which can be
used by udmabuf and/or other drivers in the future?

Thanks,
Vivek

> 
> Jason