diff --git a/mm/mmap.c b/mm/mmap.c
index ad34641cc966c0ddf22aeaeb51f03957398859f7..7a88c5f0d3e9341c762cc73331e4c60ac138cbe6 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2775,15 +2775,6 @@ static int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len,
 				munlock_vma_pages_all(tmp);
 			}
 
-			/*
-			 * Unmapping vmas, which have VM_HUGETLB or VM_PFNMAP,
-			 * need get done with write mmap_sem held since they may
-			 * update vm_flags.
-			 */
-			if (downgrade &&
-			    (tmp->vm_flags & VM_PFNMAP))
-				downgrade = false;
-
 			tmp = tmp->vm_next;
 		}
 	}