powerpc: Fix memory hotplug with sparse vmemmap

Previous commit 46723bfa540... introduced a new config option
HAVE_BOOTMEM_INFO_NODE that ended up breaking memory hot-remove for ppc
when sparse vmemmap is not defined.

This patch defines HAVE_BOOTMEM_INFO_NODE for ppc and adds the call to
register_page_bootmem_info_node. Without this we get a BUG_ON for memory
hot remove in put_page_bootmem().

This also adds a stub for register_page_bootmem_memmap to allow ppc to build
with sparse vmemmap defined. Leaving this as a stub is fine since the same
vmemmap addresses are also handled in vmemmap_populate and as such are
properly mapped.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org> [v3.9+]

1 files changed, 1 insertions, 1 deletions

diff --git a/mm/Kconfig b/mm/Kconfig
index 026771a9b097..394838f489eb 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -183,7 +183,7 @@ config MEMORY_HOTPLUG_SPARSE
 config MEMORY_HOTREMOVE
         bool "Allow for memory hot remove"
         select MEMORY_ISOLATION
-        select HAVE_BOOTMEM_INFO_NODE if X86_64
+        select HAVE_BOOTMEM_INFO_NODE if (X86_64 || PPC64)
         depends on MEMORY_HOTPLUG && ARCH_ENABLE_MEMORY_HOTREMOVE
         depends on MIGRATION