Re: [PATCH 6/8] s390/mm: implement MEM_PHYS_ONLINE MEM_PHYS_OFFLINE memory notifiers

[David Hildenbrand]

> > > Maybe s390x should just provide a dedicate interface to add these memory
> > > blocks instead of adding them during boot and then relying on the old way of
> > > using online/offline set them online/offline.
> >
> > Existing behavior:
> > The current 'lsmem -a' command displays both online and standby memory.
> >
> > interface changes:
> > If a new interface is introduced and standby memory is no longer listed,
> > the following consequences might occur:
> >
> > 1. Running 'lsmem -a' would only show online memory, potentially leading
> >      to user complaints.
>
> That's why the new, clean way of doing it will require a world switch.
> If the admin wants the benefits of altmap/memmap allocation, it can be
> enabled.

BTW, thinking about it, I guess one could teach lsmem (and maybe chmem) 
to consult additional interfaces on s390x to show standby memory that's 
not added to the system yet.

--
Cheers,

David / dhildenb