diff --git a/mm/memory.c b/mm/memory.c
index d10e616d7389..75d7959b835b 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1815,9 +1815,16 @@ static void unmap_single_vma(struct mmu_gather *tlb,
 	if (vma->vm_file)
 		uprobe_munmap(vma, start, end);
 
-	if (unlikely(vma->vm_flags & VM_PFNMAP))
+	if (unlikely(vma->vm_flags & VM_PFNMAP)) {
+		if (!mm_wr_locked)
+			mmap_read_lock(vma->vm_mm);
+
 		untrack_pfn(vma, 0, 0, mm_wr_locked);
 
+		if (!mm_wr_locked)
+			mmap_read_unlock(vma->vm_mm);
+	}
+
 	if (start != end) {
 		if (unlikely(is_vm_hugetlb_page(vma))) {
 			/*