diff --git a/sys/compat/linuxkpi/common/include/linux/fs.h b/sys/compat/linuxkpi/common/include/linux/fs.h
--- a/sys/compat/linuxkpi/common/include/linux/fs.h
+++ b/sys/compat/linuxkpi/common/include/linux/fs.h
@@ -245,6 +245,12 @@
 	return 0;
 }
 
+static inline int
+simple_open(struct inode *inode, struct file *filp)
+{
+	return 0;
+}
+
 extern unsigned int linux_iminor(struct inode *);
 #define	iminor(...) linux_iminor(__VA_ARGS__)