return kmem_cache_alloc(zero_cache, GFP_KERNEL); 
return kmem_cache_alloc(pgtable_cache[PGD_CACHE_NUM], GFP_KERNEL); 
pgd_alloc(struct mm_struct *mm){	return kmem_cache_alloc(zero_cache, GFP_KERNEL);}
10457	/local/tlutelli/issta_data/temp/c/2005_temp/2005/10457/e28f7faf05159f1cfd564596f5e6178edba6bd49/pgalloc.h/buggy/include/asm-ppc64/pgalloc.h