diff --git a/include/linux.h b/include/linux.h
index 7bf59e0..ee25ec9 100644
--- a/include/linux.h
+++ b/include/linux.h
@@ -21,6 +21,7 @@
 #include <asm/types.h>
 #include <mntent.h>
 #include <fcntl.h>
+#include <signal.h> /* For SIGKILL */
 #if defined(HAVE_FALLOCATE)
 #include <linux/falloc.h>
 #endif