diff --git a/sys/amd64/amd64/mp_machdep.c b/sys/amd64/amd64/mp_machdep.c
index 1b211026e386..97ac67edf595 100644
--- a/sys/amd64/amd64/mp_machdep.c
+++ b/sys/amd64/amd64/mp_machdep.c
@@ -280,7 +280,7 @@ init_secondary(void)
 	}
 
 	if (!fred) {
-		/* The DB# stack, used for for IDT, runs on IST4. */
+		/* The DB# stack, used for IDT, runs on IST4. */
 		np = ((struct nmi_pcpu *)&dbg_stack[DBG_STACK_SIZE]) - 1;
 		np->np_pcpu = (register_t)pc;
 		pc->pc_common_tss.tss_ist4 = (long)np;