diff --git a/include/linux/mm.h b/include/linux/mm.h
index acdccbe9b96b..4d5ab70b1f6d 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2637,8 +2637,6 @@ extern bool arch_has_descending_max_zone_pfns(void);
 /* nommu.c */
 extern atomic_long_t mmap_pages_allocated;
 extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);
-/* maple_tree */
-void vma_store(struct mm_struct *mm, struct vm_area_struct *vma);
 
 /* interval_tree.c */
 void vma_interval_tree_insert(struct vm_area_struct *node,
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
index aca874d33fe6..74de6b3f6c8c 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -8,6 +8,7 @@
 #include <linux/mm_types.h>
 #include <linux/gfp.h>
 #include <linux/sync_core.h>
+#include <linux/maple_tree.h>
 
 /*
  * Routines for handling mm_structs
@@ -78,6 +79,8 @@ static inline void mmdrop_sched(struct mm_struct *mm)
 }
 #endif
 
+void mm_set_in_rcu(struct mm_struct *mm);
+
 /**
  * mmget() - Pin the address space associated with a &struct mm_struct.
  * @mm: The address space to pin.
@@ -96,11 +99,21 @@ static inline void mmdrop_sched(struct mm_struct *mm)
  */
 static inline void mmget(struct mm_struct *mm)
 {
+	if (!mt_in_rcu(&mm->mm_mt))
+		mm_set_in_rcu(mm);
 	atomic_inc(&mm->mm_users);
 }
 
 static inline bool mmget_not_zero(struct mm_struct *mm)
 {
+	/*
+	 * There is a race below during task tear down that can cause the maple
+	 * tree to enter rcu mode with only a single user.  If this race
+	 * happens, the result would be that the maple tree nodes would remain
+	 * active for an extra RCU read cycle.
+	 */
+	if (!mt_in_rcu(&mm->mm_mt))
+		mm_set_in_rcu(mm);
 	return atomic_inc_not_zero(&mm->mm_users);
 }
 
diff --git a/kernel/fork.c b/kernel/fork.c
index cc9bb95c7678..c9f8465d8ae2 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -374,6 +374,16 @@ void vm_area_free(struct vm_area_struct *vma)
 	kmem_cache_free(vm_area_cachep, vma);
 }
 
+void mm_set_in_rcu(struct mm_struct *mm)
+{
+	if (!mt_in_rcu(&mm->mm_mt))
+		return;
+	mmap_write_lock(mm);
+	mm->mm_mt.ma_flags |= MT_FLAGS_USE_RCU;
+	mmap_write_unlock(mm);
+}
+EXPORT_SYMBOL(mm_set_in_rcu);
+
 static void account_kernel_stack(struct task_struct *tsk, int account)
 {
 	void *stack = task_stack_page(tsk);
@@ -491,7 +501,9 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 	struct vm_area_struct *mpnt, *tmp, *prev, **pprev;
 	struct rb_node **rb_link, *rb_parent;
 	int retval;
-	unsigned long charge;
+	unsigned long charge = 0;
+	MA_STATE(old_mas, &oldmm->mm_mt, 0, 0);
+	MA_STATE(mas, &mm->mm_mt, 0, 0);
 	LIST_HEAD(uf);
 
 	uprobe_start_dup_mmap();
@@ -525,7 +537,12 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 		goto out;
 
 	prev = NULL;
-	for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) {
+
+	retval = mas_entry_count(&mas, oldmm->map_count);
+	if (retval)
+		goto out;
+
+	mas_for_each(&old_mas, mpnt, ULONG_MAX) {
 		struct file *file;
 
 		if (mpnt->vm_flags & VM_DONTCOPY) {
@@ -539,7 +556,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 		 */
 		if (fatal_signal_pending(current)) {
 			retval = -EINTR;
-			goto out;
+			goto loop_out;
 		}
 		if (mpnt->vm_flags & VM_ACCOUNT) {
 			unsigned long len = vma_pages(mpnt);
@@ -605,7 +622,9 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 		rb_parent = &tmp->vm_rb;
 
 		/* Link the vma into the MT */
-		vma_store(mm, tmp);
+		mas.index = tmp->vm_start;
+		mas.last = tmp->vm_end - 1;
+		mas_store(&mas, tmp);
 
 		mm->map_count++;
 		if (!(tmp->vm_flags & VM_WIPEONFORK))
@@ -615,10 +634,13 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 			tmp->vm_ops->open(tmp);
 
 		if (retval)
-			goto out;
+			goto loop_out;
+
 	}
 	/* a new mm has just been created */
 	retval = arch_dup_mmap(oldmm, mm);
+loop_out:
+	mas_destroy(&mas);
 out:
 	mmap_write_unlock(mm);
 	flush_tlb_mm(oldmm);
@@ -634,7 +656,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 fail_nomem:
 	retval = -ENOMEM;
 	vm_unacct_memory(charge);
-	goto out;
+	goto loop_out;
 }
 
 static inline int mm_alloc_pgd(struct mm_struct *mm)
@@ -1111,6 +1133,7 @@ static inline void __mmput(struct mm_struct *mm)
 {
 	VM_BUG_ON(atomic_read(&mm->mm_users));
 
+	mt_clear_in_rcu(&mm->mm_mt);
 	uprobe_clear_state(mm);
 	exit_aio(mm);
 	ksm_exit(mm);
