aboutsummaryrefslogtreecommitdiffstats
path: root/mm/memory.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/memory.c')
-rw-r--r--mm/memory.c21
1 files changed, 9 insertions, 12 deletions
diff --git a/mm/memory.c b/mm/memory.c
index ce22a250926f..61e66f026563 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1359,7 +1359,7 @@ split_fallthrough:
1359 */ 1359 */
1360 mark_page_accessed(page); 1360 mark_page_accessed(page);
1361 } 1361 }
1362 if (flags & FOLL_MLOCK) { 1362 if ((flags & FOLL_MLOCK) && (vma->vm_flags & VM_LOCKED)) {
1363 /* 1363 /*
1364 * The preliminary mapping check is mainly to avoid the 1364 * The preliminary mapping check is mainly to avoid the
1365 * pointless overhead of lock_page on the ZERO_PAGE 1365 * pointless overhead of lock_page on the ZERO_PAGE
@@ -1412,9 +1412,8 @@ no_page_table:
1412 1412
1413static inline int stack_guard_page(struct vm_area_struct *vma, unsigned long addr) 1413static inline int stack_guard_page(struct vm_area_struct *vma, unsigned long addr)
1414{ 1414{
1415 return (vma->vm_flags & VM_GROWSDOWN) && 1415 return stack_guard_page_start(vma, addr) ||
1416 (vma->vm_start == addr) && 1416 stack_guard_page_end(vma, addr+PAGE_SIZE);
1417 !vma_stack_continue(vma->vm_prev, addr);
1418} 1417}
1419 1418
1420/** 1419/**
@@ -1551,13 +1550,6 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
1551 continue; 1550 continue;
1552 } 1551 }
1553 1552
1554 /*
1555 * If we don't actually want the page itself,
1556 * and it's the stack guard page, just skip it.
1557 */
1558 if (!pages && stack_guard_page(vma, start))
1559 goto next_page;
1560
1561 do { 1553 do {
1562 struct page *page; 1554 struct page *page;
1563 unsigned int foll_flags = gup_flags; 1555 unsigned int foll_flags = gup_flags;
@@ -1574,6 +1566,11 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
1574 int ret; 1566 int ret;
1575 unsigned int fault_flags = 0; 1567 unsigned int fault_flags = 0;
1576 1568
1569 /* For mlock, just skip the stack guard page. */
1570 if (foll_flags & FOLL_MLOCK) {
1571 if (stack_guard_page(vma, start))
1572 goto next_page;
1573 }
1577 if (foll_flags & FOLL_WRITE) 1574 if (foll_flags & FOLL_WRITE)
1578 fault_flags |= FAULT_FLAG_WRITE; 1575 fault_flags |= FAULT_FLAG_WRITE;
1579 if (nonblocking) 1576 if (nonblocking)
@@ -3396,7 +3393,7 @@ int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
3396 * run pte_offset_map on the pmd, if an huge pmd could 3393 * run pte_offset_map on the pmd, if an huge pmd could
3397 * materialize from under us from a different thread. 3394 * materialize from under us from a different thread.
3398 */ 3395 */
3399 if (unlikely(__pte_alloc(mm, vma, pmd, address))) 3396 if (unlikely(pmd_none(*pmd)) && __pte_alloc(mm, vma, pmd, address))
3400 return VM_FAULT_OOM; 3397 return VM_FAULT_OOM;
3401 /* if an huge pmd materialized from under us just retry later */ 3398 /* if an huge pmd materialized from under us just retry later */
3402 if (unlikely(pmd_trans_huge(*pmd))) 3399 if (unlikely(pmd_trans_huge(*pmd)))