hack: printf() is too easy to use.
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 13bc08a..3b01c5b 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -871,4 +871,6 @@
 	 /* OTHER_WRITABLE?  Generally considered a bad idea. */		\
 	 BUILD_BUG_ON_ZERO((perms) & 2) +					\
 	 (perms))
+
+#define printf(a...) printk(a)
 #endif