diff --git a/internal/sm2ec/p256_asm_s390x.s b/internal/sm2ec/p256_asm_s390x.s
index cd9a6d8..f0100d8 100644
--- a/internal/sm2ec/p256_asm_s390x.s
+++ b/internal/sm2ec/p256_asm_s390x.s
@@ -344,7 +344,7 @@ TEXT ·p256FromMont(SB), NOSPLIT, $0
 	MOVD  $p256<>+0x00(SB), CPOOL
 	VL    16(CPOOL), PL
 	VL    0(CPOOL), PH
-	VL    48(CPOOL), SEL1
+	VL    32(CPOOL), SEL1
 
 	VL   (0*16)(x_ptr), T0
 	VPDI $0x4, T0, T0, T0