diff --git a/libc/kernel/uapi/linux/magic.h b/libc/kernel/uapi/linux/magic.h
index 479ae81..6d583f3 100644
--- a/libc/kernel/uapi/linux/magic.h
+++ b/libc/kernel/uapi/linux/magic.h
@@ -100,4 +100,5 @@
 #define DEVMEM_MAGIC 0x454d444d
 #define Z3FOLD_MAGIC 0x33
 #define PPC_CMM_MAGIC 0xc7571590
+#define SECRETMEM_MAGIC 0x5345434d
 #endif