From e544a4e74e02108035de69f97fde7bdf19dba978 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Wed, 10 Dec 2014 15:44:22 -0800 Subject: [PATCH] thp: do not mark zero-page pmd write-protected explicitly Zero pages can be used only in anonymous mappings, which never have writable vma->vm_page_prot: see protection_map in mm/mmap.c and __PX1X definitions. Let's drop redundant pmd_wrprotect() in set_huge_zero_page(). Signed-off-by: "Kirill A. Shutemov" Cc: Andrea Arcangeli Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/huge_memory.c | 1 - 1 file changed, 1 deletion(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index de98415..5b2c687 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -784,7 +784,6 @@ static bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm, if (!pmd_none(*pmd)) return false; entry = mk_pmd(zero_page, vma->vm_page_prot); - entry = pmd_wrprotect(entry); entry = pmd_mkhuge(entry); pgtable_trans_huge_deposit(mm, pmd, pgtable); set_pmd_at(mm, haddr, pmd, entry); -- 2.7.4