From: David Hildenbrand <david@xxxxxxxxxx> Subject: mm/page_ext.c: drop pfn_present() check when onlining Since commit c5e79ef561b0 ("mm/memory_hotplug.c: don't allow to online/offline memory blocks with holes") we disallow to offline any memory with holes. As all boot memory is online and hotplugged memory cannot contain holes, we never online memory with holes. This present check can be dropped. Link: http://lkml.kernel.org/r/20200127110424.5757-4-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx> Cc: Dan Williams <dan.j.williams@xxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_ext.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) --- a/mm/page_ext.c~mm-page_extc-drop-pfn_present-check-when-onlining +++ a/mm/page_ext.c @@ -303,11 +303,8 @@ static int __meminit online_page_ext(uns VM_BUG_ON(!node_state(nid, N_ONLINE)); } - for (pfn = start; !fail && pfn < end; pfn += PAGES_PER_SECTION) { - if (!pfn_in_present_section(pfn)) - continue; + for (pfn = start; !fail && pfn < end; pfn += PAGES_PER_SECTION) fail = init_section_page_ext(pfn, nid); - } if (!fail) return 0; _