diff --git a/sys/src/9/pc/l.s b/sys/src/9/pc/l.s
index 0808bd5c2..663107e7a 100644
--- a/sys/src/9/pc/l.s
+++ b/sys/src/9/pc/l.s
@@ -67,9 +67,9 @@ TEXT _multibootentry(SB), $0
 	SUBL	DI, CX
 	ADDL	CX, SI
 	ADDL	CX, DI
+	INCL	CX	/* one more for post decrement */
 	STD
 	REP; MOVSB
-	CLD
 	ADDL	$KZERO, BX
 	MOVL	BX, multiboot-KZERO(SB)
 	MOVL	$_startPADDR(SB), AX
diff --git a/sys/src/9/pc64/l.s b/sys/src/9/pc64/l.s
index f4c066a3c..78171a114 100644
--- a/sys/src/9/pc64/l.s
+++ b/sys/src/9/pc64/l.s
@@ -62,9 +62,9 @@ TEXT _multibootentry<>(SB), 1, $-4
 	SUBL	DI, CX
 	ADDL	CX, SI
 	ADDL	CX, DI
+	INCL	CX	/* one more for post decrement */
 	STD
 	REP; MOVSB
-	CLD
 	MOVL	BX, multibootptr-KZERO(SB)
 	MOVL	$_protected<>-KZERO(SB), AX
 	JMP*	AX