Hello Junjiro, I just built 3.12.31 and there is a bug introduced with differences in the mm/Makefile. It is very trivial. --- linux-3.12.31/mm/Makefile.orig 2014-10-28 08:09:10.781714774 +1000 +++ linux-3.12.31/mm/Makefile 2014-10-28 08:17:17.688376084 +1000 @@ -17,7 +17,7 @@   util.o mmzone.o vmstat.o backing-dev.o \   mm_init.o mmu_context.o percpu.o slab_common.o \   compaction.o balloon_compaction.o vmacache.o \ -  interval_tree.o list_lru.o $(mmu-y) +  interval_tree.o list_lru.o prfile.o $(mmu-y)   obj-y += init-mm.o  Regards, Michael Amadio Puppy Slacko developer.
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