3 files changed, 12 insertions, 15 deletions

diff --git a/mm/internal.h b/mm/internal.h
index b61034bd50f5..89a5a794d68f 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -1154,17 +1154,6 @@ 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 5c757fba8858..a7025ed5c65b 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -374,6 +374,8 @@ 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
@@ -395,6 +397,8 @@ 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);
@@ -1744,7 +1748,8 @@ 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 1971bfffcc03..4f1cb814586d 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -3294,10 +3294,11 @@ 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();
@@ -3332,11 +3333,13 @@ 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);