On Mon 27-05-19 13:11:43, David Hildenbrand wrote: > ZONE_DEVICE is not yet supported, fail if an altmap is passed, so we > don't forget arch_add_memory()/arch_remove_memory() when unlocking > support. Why do we need this? Sure ZONE_DEVICE is not supported for s390 and so might be the case for other arches which support hotplug. I do not see much point in adding warning to each of them. > Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> > Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Cc: Michal Hocko <mhocko@xxxxxxxx> > Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> > Cc: David Hildenbrand <david@xxxxxxxxxx> > Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> > Cc: Oscar Salvador <osalvador@xxxxxxxx> > Suggested-by: Dan Williams <dan.j.williams@xxxxxxxxx> > Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> > --- > arch/s390/mm/init.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c > index 14d1eae9fe43..d552e330fbcc 100644 > --- a/arch/s390/mm/init.c > +++ b/arch/s390/mm/init.c > @@ -226,6 +226,9 @@ int arch_add_memory(int nid, u64 start, u64 size, > unsigned long size_pages = PFN_DOWN(size); > int rc; > > + if (WARN_ON_ONCE(restrictions->altmap)) > + return -EINVAL; > + > rc = vmem_add_mapping(start, size); > if (rc) > return rc; > -- > 2.20.1 > -- Michal Hocko SUSE Labs
