Re: [PATCH v4 3/9] mm/memory_hotplug: export mhp_get_default_online_type

[Gregory Price <gourry@gourry.net>]

On Tue, Jun 09, 2026 at 11:52:21AM +0200, David Hildenbrand (Arm) wrote:
> On 6/5/26 23:19, Gregory Price wrote:
> > Drivers which may pass hotplug policy down to DAX need MMOP_ symbols
> > and the mhp_get_default_online_type function for hotplug use cases.
> > 
> > Some drivers (cxl) co-mingle their hotplug and devdax use-cases into
> > the same driver code, and chose the dax_kmem path as the default driver
> > path - making it difficult to require hotplug as a predicate to building
> > the overall driver (it may break other non-hotplug use-cases).
> > 
> > Export mhp_get_default_online_type function to allow these drivers to
> > build when hotplug is disabled and still use the DAX use case.
> > 
> > In the built-out case we simply return MMOP_OFFLINE as it's
> 
> Ah, you mean without CONFIG_MEMORY_HOTPLUG
> 

Yeah i'll update the commit message, thanks!

> > non-destructive.  The internal function can never return -1 either,
> > so we choose this to allow for defining the function with 'enum mmop'.
> 
> Acked-by: David Hildenbrand (Arm) <david@kernel.org>
> 
> -- 
> Cheers,
> 
> David