diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 4b53dc4a3266..390e4b7d9cb9 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -786,6 +786,8 @@ void mremap_userfaultfd_fail(struct vm_userfaultfd_ctx *vm_ctx)
 	if (!ctx)
 		return;
 
+	atomic_dec(&ctx->mmap_changing);
+	VM_WARN_ON_ONCE(atomic_read(&ctx->mmap_changing) < 0);
 	userfaultfd_ctx_put(ctx);
 }