Hi Andrew, After merging the akpm-current tree, today's linux-next build (powerpc pseries_le_defconfig) failed like this: mm/huge_memory.c:1089:9: error: implicit declaration of function 'pud_mkyoung' [-Werror=implicit-function-declaration] _pud = pud_mkyoung(pud_mkdirty(*pud)); ^ mm/huge_memory.c:1089:21: error: implicit declaration of function 'pud_mkdirty' [-Werror=implicit-function-declaration] _pud = pud_mkyoung(pud_mkdirty(*pud)); ^ mm/huge_memory.c:1089:7: error: incompatible types when assigning to type 'pud_t {aka struct <anonymous>}' from type 'int' _pud = pud_mkyoung(pud_mkdirty(*pud)); ^ mm/huge_memory.c:1090:6: error: implicit declaration of function 'pudp_set_access_flags' [-Werror=implicit-function-declaration] if (pudp_set_access_flags(vma, addr & HPAGE_PUD_MASK, ^ mm/huge_memory.c:1092:3: error: implicit declaration of function 'update_mmu_cache_pud' [-Werror=implicit-function-declaration] update_mmu_cache_pud(vma, addr, pud); ^ mm/huge_memory.c: In function 'follow_devmap_pud': mm/huge_memory.c:1137:22: error: implicit declaration of function 'pud_pfn' [-Werror=implicit-function-declaration] unsigned long pfn = pud_pfn(*pud); ^ Caused by commit a27da20ed50e ("mm: add support for PUD-sized transparent hugepages") Some bit have not been protected with CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD ... I added the following (ugly) patch: From: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> Date: Wed, 3 Feb 2016 15:07:54 +1100 Subject: [PATCH] mm: add support for PUD-sized transparent hugepages fix Signed-off-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> --- mm/huge_memory.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 1632e02f859c..bad79b236ede 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1074,6 +1074,7 @@ static void touch_pmd(struct vm_area_struct *vma, unsigned long addr, update_mmu_cache_pmd(vma, addr, pmd); } +#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD static void touch_pud(struct vm_area_struct *vma, unsigned long addr, pud_t *pud) { @@ -1091,6 +1092,7 @@ static void touch_pud(struct vm_area_struct *vma, unsigned long addr, pud, _pud, 1)) update_mmu_cache_pud(vma, addr, pud); } +#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr, pmd_t *pmd, int flags) @@ -1131,6 +1133,7 @@ struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr, return page; } +#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr, pud_t *pud, int flags) { @@ -1169,6 +1172,7 @@ struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr, return page; } +#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm, pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr, @@ -1974,6 +1978,7 @@ spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma) return NULL; } +#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD /* * Returns true if a given pud maps a thp, false otherwise. * @@ -1989,6 +1994,7 @@ spinlock_t *__pud_trans_huge_lock(pud_t *pud, struct vm_area_struct *vma) spin_unlock(ptl); return NULL; } +#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ #define VM_NO_THP (VM_SPECIAL | VM_HUGETLB | VM_SHARED | VM_MAYSHARE) -- 2.6.4 -- Cheers, Stephen Rothwell -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html