1 files changed, 45 insertions, 6 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index ad499f7b767f..d5475fbf5729 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1518,7 +1518,8 @@ static inline int accountable_mapping(struct file *file, vm_flags_t vm_flags)
  */
 static unsigned long unmapped_area(struct vm_unmapped_area_info *info)
 {
-	unsigned long length, gap;
+	unsigned long length, gap, low_limit;
+	struct vm_area_struct *tmp;
 
 	MA_STATE(mas, &current->mm->mm_mt, 0, 0);
 
@@ -1527,12 +1528,29 @@ static unsigned long unmapped_area(struct vm_unmapped_area_info *info)
 	if (length < info->length)
 		return -ENOMEM;
 
-	if (mas_empty_area(&mas, info->low_limit, info->high_limit - 1,
-				  length))
+	low_limit = info->low_limit;
+retry:
+	if (mas_empty_area(&mas, low_limit, info->high_limit - 1, length))
 		return -ENOMEM;
 
 	gap = mas.index;
 	gap += (info->align_offset - gap) & info->align_mask;
+	tmp = mas_next(&mas, ULONG_MAX);
+	if (tmp && (tmp->vm_flags & VM_GROWSDOWN)) { /* Avoid prev check if possible */
+		if (vm_start_gap(tmp) < gap + length - 1) {
+			low_limit = tmp->vm_end;
+			mas_reset(&mas);
+			goto retry;
+		}
+	} else {
+		tmp = mas_prev(&mas, 0);
+		if (tmp && vm_end_gap(tmp) > gap) {
+			low_limit = vm_end_gap(tmp);
+			mas_reset(&mas);
+			goto retry;
+		}
+	}
+
 	return gap;
 }
 
@@ -1548,7 +1566,8 @@ static unsigned long unmapped_area(struct vm_unmapped_area_info *info)
  */
 static unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info)
 {
-	unsigned long length, gap;
+	unsigned long length, gap, high_limit, gap_end;
+	struct vm_area_struct *tmp;
 
 	MA_STATE(mas, &current->mm->mm_mt, 0, 0);
 	/* Adjust search length to account for worst case alignment overhead */
@@ -1556,12 +1575,31 @@ static unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info)
 	if (length < info->length)
 		return -ENOMEM;
 
-	if (mas_empty_area_rev(&mas, info->low_limit, info->high_limit - 1,
+	high_limit = info->high_limit;
+retry:
+	if (mas_empty_area_rev(&mas, info->low_limit, high_limit - 1,
 				length))
 		return -ENOMEM;
 
 	gap = mas.last + 1 - info->length;
 	gap -= (gap - info->align_offset) & info->align_mask;
+	gap_end = mas.last;
+	tmp = mas_next(&mas, ULONG_MAX);
+	if (tmp && (tmp->vm_flags & VM_GROWSDOWN)) { /* Avoid prev check if possible */
+		if (vm_start_gap(tmp) <= gap_end) {
+			high_limit = vm_start_gap(tmp);
+			mas_reset(&mas);
+			goto retry;
+		}
+	} else {
+		tmp = mas_prev(&mas, 0);
+		if (tmp && vm_end_gap(tmp) > gap) {
+			high_limit = tmp->vm_start;
+			mas_reset(&mas);
+			goto retry;
+		}
+	}
+
 	return gap;
 }
 
@@ -2277,7 +2315,7 @@ do_vmi_align_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma,
 	int count = 0;
 	int error = -ENOMEM;
 	MA_STATE(mas_detach, &mt_detach, 0, 0);
-	mt_init_flags(&mt_detach, MT_FLAGS_LOCK_EXTERN);
+	mt_init_flags(&mt_detach, vmi->mas.tree->ma_flags & MT_FLAGS_LOCK_MASK);
 	mt_set_external_lock(&mt_detach, &mm->mmap_lock);
 
 	/*
@@ -3037,6 +3075,7 @@ void exit_mmap(struct mm_struct *mm)
 	 */
 	set_bit(MMF_OOM_SKIP, &mm->flags);
 	mmap_write_lock(mm);
+	mt_clear_in_rcu(&mm->mm_mt);
 	free_pgtables(&tlb, &mm->mm_mt, vma, FIRST_USER_ADDRESS,
 		      USER_PGTABLES_CEILING);
 	tlb_finish_mmu(&tlb);