sparc64: Fix bugs in get_user_pages_fast() wrt. THP.

The large PMD path needs to check _PAGE_VALID not _PAGE_PRESENT, to decide if it needs to bail and return 0. pmd_large() should therefore just check _PAGE_PMD_HUGE. Calls to gup_huge_pmd() are guarded with a check of pmd_large(), so we just need to add a valid bit check. Signed-off-by: David S. Miller <davem@davemloft.net>
mariux64 · May 4, 2014 · 04df419 · 04df419
1 parent 51e5ef1
commit 04df419
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Showing 2 changed files with 2 additions and 2 deletions.
diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h
@@ -633,7 +633,7 @@ static inline unsigned long pmd_large(pmd_t pmd)
 {
 	pte_t pte = __pte(pmd_val(pmd));
 
-	return (pte_val(pte) & _PAGE_PMD_HUGE) && pte_present(pte);
+	return pte_val(pte) & _PAGE_PMD_HUGE;
 }
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE

diff --git a/arch/sparc/mm/gup.c b/arch/sparc/mm/gup.c
@@ -73,7 +73,7 @@ static int gup_huge_pmd(pmd_t *pmdp, pmd_t pmd, unsigned long addr,
 	struct page *head, *page, *tail;
 	int refs;
 
-	if (!pmd_large(pmd))
+	if (!(pmd_val(pmd) & _PAGE_VALID))
 		return 0;
 
 	if (write && !pmd_write(pmd))