Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[mirror_ubuntu-zesty-kernel.git] / mm / memory.c

diff --git a/mm/memory.c b/mm/memory.c
index 1e77da6d82c1ef8b5c96ede4c7be04c7d38771dd..1b7dc662bf9f229063cb3e7b97e8e4c22147b92b 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1307,6 +1307,9 @@ static void unmap_single_vma(struct mmu_gather *tlb,
        if (end <= vma->vm_start)
                return;
 
+       if (vma->vm_file)
+               uprobe_munmap(vma, start, end);
+
        if (unlikely(is_pfn_mapping(vma)))
                untrack_pfn_vma(vma, 0, 0);
 
@@ -2905,7 +2908,6 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
        delayacct_set_flag(DELAYACCT_PF_SWAPIN);
        page = lookup_swap_cache(entry);
        if (!page) {
-               grab_swap_token(mm); /* Contend for token _before_ read-in */
                page = swapin_readahead(entry,
                                        GFP_HIGHUSER_MOVABLE, vma, address);
                if (!page) {
@@ -2935,6 +2937,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
        }
 
        locked = lock_page_or_retry(page, mm, flags);
+
        delayacct_clear_flag(DELAYACCT_PF_SWAPIN);
        if (!locked) {
                ret |= VM_FAULT_RETRY;
@@ -3483,6 +3486,7 @@ int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
        if (unlikely(is_vm_hugetlb_page(vma)))
                return hugetlb_fault(mm, vma, address, flags);
 
+retry:
        pgd = pgd_offset(mm, address);
        pud = pud_alloc(mm, pgd, address);
        if (!pud)
@@ -3496,13 +3500,24 @@ int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
                                                          pmd, flags);
        } else {
                pmd_t orig_pmd = *pmd;
+               int ret;
+
                barrier();
                if (pmd_trans_huge(orig_pmd)) {
                        if (flags & FAULT_FLAG_WRITE &&
                            !pmd_write(orig_pmd) &&
-                           !pmd_trans_splitting(orig_pmd))
-                               return do_huge_pmd_wp_page(mm, vma, address,
-                                                          pmd, orig_pmd);
+                           !pmd_trans_splitting(orig_pmd)) {
+                               ret = do_huge_pmd_wp_page(mm, vma, address, pmd,
+                                                         orig_pmd);
+                               /*
+                                * If COW results in an oom, the huge pmd will
+                                * have been split, so retry the fault on the
+                                * pte for a smaller charge.
+                                */
+                               if (unlikely(ret & VM_FAULT_OOM))
+                                       goto retry;
+                               return ret;
+                       }
                        return 0;
                }
        }