diff --git a/sys/kern/subr_kdb.c b/sys/kern/subr_kdb.c
index df7a9ef0574..249aab4b347 100644
--- a/sys/kern/subr_kdb.c
+++ b/sys/kern/subr_kdb.c
@@ -50,7 +50,7 @@ __FBSDID("$FreeBSD$");
 #include <machine/smp.h>
 #endif
 
-bool __read_frequently kdb_active = 0;
+u_char __read_frequently kdb_active = 0;
 static void *kdb_jmpbufp = NULL;
 struct kdb_dbbe *kdb_dbbe = NULL;
 static struct pcb kdb_pcb;
diff --git a/sys/sys/kdb.h b/sys/sys/kdb.h
index 27d2475cc22..1e68c398285 100644
--- a/sys/sys/kdb.h
+++ b/sys/sys/kdb.h
@@ -59,7 +59,7 @@ struct kdb_dbbe {
 	};						\
 	DATA_SET(kdb_dbbe_set, name##_dbbe)
 
-extern bool kdb_active;			/* Non-zero while in debugger. */
+extern u_char kdb_active;		/* Non-zero while in debugger. */
 extern int debugger_on_panic;		/* enter the debugger on panic. */
 extern struct kdb_dbbe *kdb_dbbe;	/* Default debugger backend or NULL. */
 extern struct trapframe *kdb_frame;	/* Frame to kdb_trap(). */