aeb4dbdd4c
Memmap_on_memory changes the behaviour of memory hotplug to reserve the first X Mb of a memory block for the struct page array. On arm64, the size of the struct page array for a 128Mb memory block is 2Mb. However, the memory-hotplug code requires X to be pageblock aligned (4Mb). memory_hotplug.memmap_on_memory="force" informs the memory-hotplug core to round up the size of the memory reserved for struct page array to meet this 4Mb requirement, even though only 2Mb will actually be used. This is preferred over allocating the struct page array from ZONE_NORMAL because adding additional memory into ZONE_NORMAL is not supported on this target. Change-Id: I9544b58c202cecddbe80be67a24a1115b162e478 Signed-off-by: Patrick Daly <quic_pdaly@quicinc.com>