[PATCH 2/2] mm: fix undefined reference to `.kernel_map_pages' on PPC builds

[Akinobu Mita]

2015-01-21 9:07 GMT+09:00 Andrew Morton <akpm at linux-foundation.org>:
> On Tue, 20 Jan 2015 15:01:50 -0800 josh at joshtriplett.org wrote:
>
>> On Tue, Jan 20, 2015 at 02:02:00PM -0600, Kim Phillips wrote:
>> > It's possible to configure DEBUG_PAGEALLOC without PAGE_POISONING on
>> > ppc.  Fix building the generic kernel_map_pages() implementation in
>> > this case:
>> >
>> >   LD      init/built-in.o
>> > mm/built-in.o: In function `free_pages_prepare':
>> > mm/page_alloc.c:770: undefined reference to `.kernel_map_pages'
>> > mm/built-in.o: In function `prep_new_page':
>> > mm/page_alloc.c:933: undefined reference to `.kernel_map_pages'
>> > mm/built-in.o: In function `map_pages':
>> > mm/compaction.c:61: undefined reference to `.kernel_map_pages'
>> > make: *** [vmlinux] Error 1

kernel_map_pages() is static inline function since commit 031bc5743f15
("mm/debug-pagealloc: make debug-pagealloc boottime configurable").

But there is old declaration in 'arch/powerpc/include/asm/cacheflush.h'.
Removing it or changing s/kernel_map_pages/__kernel_map_pages/ in this
header file or something can fix this problem?

The architecture which has ARCH_SUPPORTS_DEBUG_PAGEALLOC
including PPC should not build mm/debug-pagealloc.o