[PATCH] hugetlb: check p?d_present in huge_pte_offset()

For demand faulting, we cannot assume that the page tables will be
populated.  Do what the rest of the architectures do and test p?d_present()
while walking down the page table.

Signed-off-by: Adam Litke <agl@us.ibm.com>
Cc: <linux-mm@kvack.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Adam Litke 2005-09-03 15:55:01 -07:00 committed by Linus Torvalds
parent 7bf07f3d4b
commit 02b0ccef90

View File

@ -46,8 +46,11 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
pmd_t *pmd = NULL;
pgd = pgd_offset(mm, addr);
pud = pud_offset(pgd, addr);
pmd = pmd_offset(pud, addr);
if (pgd_present(*pgd)) {
pud = pud_offset(pgd, addr);
if (pud_present(*pud))
pmd = pmd_offset(pud, addr);
}
return (pte_t *) pmd;
}