path: root/mm
diff options
authorAdam Litke <agl@us.ibm.com>2007-12-10 15:49:28 -0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-12-10 19:43:55 -0800
commit72fad7139b6829f71d7f41f39eb30da5760d90a8 (patch)
tree4f33b824f37923b8f65f2a0542a2e9dcb110c22e /mm
parentspi_imx: fix typo in description (diff)
hugetlb: handle write-protection faults in follow_hugetlb_page
The follow_hugetlb_page() fix I posted (merged as git commit 5b23dbe8173c212d6a326e35347b038705603d39) missed one case. If the pte is present, but not writable and write access is requested by the caller to get_user_pages(), the code will do the wrong thing. Rather than calling hugetlb_fault to make the pte writable, it notes the presence of the pte and continues. This simple one-liner makes sure we also fault on the pte for this case. Please apply. Signed-off-by: Adam Litke <agl@us.ibm.com> Acked-by: Dave Kleikamp <shaggy@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 6121b57bbe96..6f978218c2c8 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -907,7 +907,7 @@ int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
pte = huge_pte_offset(mm, vaddr & HPAGE_MASK);
- if (!pte || pte_none(*pte)) {
+ if (!pte || pte_none(*pte) || (write && !pte_write(*pte))) {
int ret;