From c177c81e09e517bbf75b67762cdab1b83aba6976 Mon Sep 17 00:00:00 2001 From: Naoya Horiguchi Date: Wed, 4 Jun 2014 16:05:35 -0700 Subject: hugetlb: restrict hugepage_migration_support() to x86_64 Currently hugepage migration is available for all archs which support pmd-level hugepage, but testing is done only for x86_64 and there're bugs for other archs. So to avoid breaking such archs, this patch limits the availability strictly to x86_64 until developers of other archs get interested in enabling this feature. Simply disabling hugepage migration on non-x86_64 archs is not enough to fix the reported problem where sys_move_pages() hits the BUG_ON() in follow_page(FOLL_GET), so let's fix this by checking if hugepage migration is supported in vma_migratable(). Signed-off-by: Naoya Horiguchi Reported-by: Michael Ellerman Tested-by: Michael Ellerman Acked-by: Hugh Dickins Cc: Benjamin Herrenschmidt Cc: Tony Luck Cc: Russell King Cc: Martin Schwidefsky Cc: James Hogan Cc: Ralf Baechle Cc: David Miller Cc: [3.12+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/mm/hugetlbpage.c | 5 ----- 1 file changed, 5 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c index 0727a55d87d9..0ff66a7e29bb 100644 --- a/arch/s390/mm/hugetlbpage.c +++ b/arch/s390/mm/hugetlbpage.c @@ -220,11 +220,6 @@ int pud_huge(pud_t pud) return 0; } -int pmd_huge_support(void) -{ - return 1; -} - struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address, pmd_t *pmdp, int write) { -- cgit v1.2.3-59-g8ed1b