diff --git a/include/linux/mm.h b/include/linux/mm.h
index bcf7ce10e138..550ad51db238 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -994,6 +994,17 @@ static inline int vma_iter_bulk_alloc(struct vma_iterator *vmi,
 	return mas_expected_entries(&vmi->mas, count);
 }
 
+static inline int vma_iter_clear_gfp(struct vma_iterator *vmi,
+			unsigned long start, unsigned long end, gfp_t gfp)
+{
+	__mas_set_range(&vmi->mas, start, end - 1);
+	mas_store_gfp(&vmi->mas, NULL, gfp);
+	if (unlikely(mas_is_err(&vmi->mas)))
+		return -ENOMEM;
+
+	return 0;
+}
+
 /* Free any unused preallocations */
 static inline void vma_iter_free(struct vma_iterator *vmi)
 {
diff --git a/kernel/fork.c b/kernel/fork.c
index 177ce7438db6..5ac80eb22dce 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -650,7 +650,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 	int retval;
 	unsigned long charge = 0;
 	LIST_HEAD(uf);
-	VMA_ITERATOR(old_vmi, oldmm, 0);
 	VMA_ITERATOR(vmi, mm, 0);
 
 	uprobe_start_dup_mmap();
@@ -678,16 +677,22 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 		goto out;
 	khugepaged_fork(mm, oldmm);
 
-	retval = vma_iter_bulk_alloc(&vmi, oldmm->map_count);
-	if (retval)
+	/* Use __mt_dup() to efficiently build an identical maple tree. */
+	retval = __mt_dup(&oldmm->mm_mt, &mm->mm_mt, GFP_KERNEL);
+	if (unlikely(retval))
 		goto out;
 
 	mt_clear_in_rcu(vmi.mas.tree);
-	for_each_vma(old_vmi, mpnt) {
+	for_each_vma(vmi, mpnt) {
 		struct file *file;
 
 		vma_start_write(mpnt);
 		if (mpnt->vm_flags & VM_DONTCOPY) {
+			retval = vma_iter_clear_gfp(&vmi, mpnt->vm_start,
+						    mpnt->vm_end, GFP_KERNEL);
+			if (retval)
+				goto loop_out;
+
 			vm_stat_account(mm, mpnt->vm_flags, -vma_pages(mpnt));
 			continue;
 		}
@@ -749,9 +754,11 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 		if (is_vm_hugetlb_page(tmp))
 			hugetlb_dup_vma_private(tmp);
 
-		/* Link the vma into the MT */
-		if (vma_iter_bulk_store(&vmi, tmp))
-			goto fail_nomem_vmi_store;
+		/*
+		 * Link the vma into the MT. After using __mt_dup(), memory
+		 * allocation is not necessary here, so it cannot fail.
+		 */
+		vma_iter_bulk_store(&vmi, tmp);
 
 		mm->map_count++;
 		if (!(tmp->vm_flags & VM_WIPEONFORK))
@@ -760,15 +767,28 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 		if (tmp->vm_ops && tmp->vm_ops->open)
 			tmp->vm_ops->open(tmp);
 
-		if (retval)
+		if (retval) {
+			mpnt = vma_next(&vmi);
 			goto loop_out;
+		}
 	}
 	/* a new mm has just been created */
 	retval = arch_dup_mmap(oldmm, mm);
 loop_out:
 	vma_iter_free(&vmi);
-	if (!retval)
+	if (!retval) {
 		mt_set_in_rcu(vmi.mas.tree);
+	} else if (mpnt) {
+		/*
+		 * The entire maple tree has already been duplicated. If the
+		 * mmap duplication fails, mark the failure point with
+		 * XA_ZERO_ENTRY. In exit_mmap(), if this marker is encountered,
+		 * stop releasing VMAs that have not been duplicated after this
+		 * point.
+		 */
+		mas_set_range(&vmi.mas, mpnt->vm_start, mpnt->vm_end - 1);
+		mas_store(&vmi.mas, XA_ZERO_ENTRY);
+	}
 out:
 	mmap_write_unlock(mm);
 	flush_tlb_mm(oldmm);
@@ -778,8 +798,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 	uprobe_end_dup_mmap();
 	return retval;
 
-fail_nomem_vmi_store:
-	unlink_anon_vmas(tmp);
 fail_nomem_anon_vma_fork:
 	mpol_put(vma_policy(tmp));
 fail_nomem_policy:
diff --git a/mm/internal.h b/mm/internal.h
index ef8d787a510c..053e6a0ea838 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -1087,17 +1087,6 @@ static inline void vma_iter_clear(struct vma_iterator *vmi)
 	mas_store_prealloc(&vmi->mas, NULL);
 }
 
-static inline int vma_iter_clear_gfp(struct vma_iterator *vmi,
-			unsigned long start, unsigned long end, gfp_t gfp)
-{
-	__mas_set_range(&vmi->mas, start, end - 1);
-	mas_store_gfp(&vmi->mas, NULL, gfp);
-	if (unlikely(mas_is_err(&vmi->mas)))
-		return -ENOMEM;
-
-	return 0;
-}
-
 static inline struct vm_area_struct *vma_iter_load(struct vma_iterator *vmi)
 {
 	return mas_walk(&vmi->mas);
diff --git a/mm/memory.c b/mm/memory.c
index bfd2273cb4b4..30af0a6145bd 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -373,6 +373,8 @@ void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas,
 		 * be 0.  This will underflow and is okay.
 		 */
 		next = mas_find(mas, ceiling - 1);
+		if (unlikely(xa_is_zero(next)))
+			next = NULL;
 
 		/*
 		 * Hide vma from rmap and truncate_pagecache before freeing
@@ -394,6 +396,8 @@ void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas,
 			       && !is_vm_hugetlb_page(next)) {
 				vma = next;
 				next = mas_find(mas, ceiling - 1);
+				if (unlikely(xa_is_zero(next)))
+					next = NULL;
 				if (mm_wr_locked)
 					vma_start_write(vma);
 				unlink_anon_vmas(vma);
@@ -1734,7 +1738,8 @@ void unmap_vmas(struct mmu_gather *tlb, struct ma_state *mas,
 		unmap_single_vma(tlb, vma, start, end, &details,
 				 mm_wr_locked);
 		hugetlb_zap_end(vma, &details);
-	} while ((vma = mas_find(mas, tree_end - 1)) != NULL);
+		vma = mas_find(mas, tree_end - 1);
+	} while (vma && likely(!xa_is_zero(vma)));
 	mmu_notifier_invalidate_range_end(&range);
 }
 
diff --git a/mm/mmap.c b/mm/mmap.c
index 84e49e8bf010..6cfa7cca4999 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -3224,10 +3224,11 @@ void exit_mmap(struct mm_struct *mm)
 	arch_exit_mmap(mm);
 
 	vma = mas_find(&mas, ULONG_MAX);
-	if (!vma) {
+	if (!vma || unlikely(xa_is_zero(vma))) {
 		/* Can happen if dup_mmap() received an OOM */
 		mmap_read_unlock(mm);
-		return;
+		mmap_write_lock(mm);
+		goto destroy;
 	}
 
 	lru_add_drain();
@@ -3262,11 +3263,13 @@ void exit_mmap(struct mm_struct *mm)
 		remove_vma(vma, true);
 		count++;
 		cond_resched();
-	} while ((vma = mas_find(&mas, ULONG_MAX)) != NULL);
+		vma = mas_find(&mas, ULONG_MAX);
+	} while (vma && likely(!xa_is_zero(vma)));
 
 	BUG_ON(count != mm->map_count);
 
 	trace_exit_mmap(mm);
+destroy:
 	__mt_destroy(&mm->mm_mt);
 	mmap_write_unlock(mm);
 	vm_unacct_memory(nr_accounted);