From 4dc59be5037f059421e302890165d5ccf6a386ac Mon Sep 17 00:00:00 2001 From: David Miller Date: Wed, 2 Oct 2013 14:25:09 -0400 Subject: mm: Fix generic hugetlb pte check return type. [ Upstream commit 26794942461f438a6bc725ec7294b08a6bd782c4 ] The include/asm-generic/hugetlb.h stubs that just vector huge_pte_*() calls to the pte_*() implementations won't work in certain situations. x86 and sparc, for example, return "unsigned long" from the bit checks, and just go "return pte_val(pte) & PTE_BIT_FOO;" But since huge_pte_*() returns 'int', if any high bits on 64-bit are relevant, they get chopped off. The net effect is that we can loop forever trying to COW a huge page, because the huge_pte_write() check signals false all the time. Reported-by: Gurudas Pai Tested-by: Gurudas Pai Signed-off-by: David S. Miller Acked-by: David Rientjes Signed-off-by: Greg Kroah-Hartman --- include/asm-generic/hugetlb.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h index d06079c774a..99b490b4d05 100644 --- a/include/asm-generic/hugetlb.h +++ b/include/asm-generic/hugetlb.h @@ -6,12 +6,12 @@ static inline pte_t mk_huge_pte(struct page *page, pgprot_t pgprot) return mk_pte(page, pgprot); } -static inline int huge_pte_write(pte_t pte) +static inline unsigned long huge_pte_write(pte_t pte) { return pte_write(pte); } -static inline int huge_pte_dirty(pte_t pte) +static inline unsigned long huge_pte_dirty(pte_t pte) { return pte_dirty(pte); } -- cgit v1.2.3