diff --git a/arch/um/include/asm/io.h b/arch/um/include/asm/io.h
index cef03e3aa0f9..6ce18d343997 100644
--- a/arch/um/include/asm/io.h
+++ b/arch/um/include/asm/io.h
@@ -1,6 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _ASM_UM_IO_H
 #define _ASM_UM_IO_H
+#include <linux/types.h>
 
 #define ioremap ioremap
 static inline void __iomem *ioremap(phys_addr_t offset, size_t size)