diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c
index b42395d24cba50b0e30c39ab6275cdaa1eca3235..42ad57365eca5bd98fd412b0e01daca81943981b 100644
--- a/net/smc/smc_cdc.c
+++ b/net/smc/smc_cdc.c
@@ -82,7 +82,7 @@ static inline void smc_cdc_add_pending_send(struct smc_connection *conn,
 		sizeof(struct smc_cdc_msg) > SMC_WR_BUF_SIZE,
 		"must increase SMC_WR_BUF_SIZE to at least sizeof(struct smc_cdc_msg)");
 	BUILD_BUG_ON_MSG(
-		offsetof(struct smc_cdc_msg, reserved) > SMC_WR_TX_SIZE,
+		sizeof(struct smc_cdc_msg) != SMC_WR_TX_SIZE,
 		"must adapt SMC_WR_TX_SIZE to sizeof(struct smc_cdc_msg); if not all smc_wr upper layer protocols use the same message size any more, must start to set link->wr_tx_sges[i].length on each individual smc_wr_tx_send()");
 	BUILD_BUG_ON_MSG(
 		sizeof(struct smc_cdc_tx_pend) > SMC_WR_TX_PEND_PRIV_SIZE,
diff --git a/net/smc/smc_cdc.h b/net/smc/smc_cdc.h
index ab240b37ad11459ba552422e6b87078b358a008c..d2012fd221001030662dbe796ee4e0b9c8dfbedd 100644
--- a/net/smc/smc_cdc.h
+++ b/net/smc/smc_cdc.h
@@ -48,7 +48,7 @@ struct smc_cdc_msg {
 	struct smc_cdc_producer_flags	prod_flags;
 	struct smc_cdc_conn_state_flags	conn_state_flags;
 	u8				reserved[18];
-} __aligned(8);
+} __packed;					/* format defined in RFC7609 */
 
 static inline bool smc_cdc_rxed_any_close(struct smc_connection *conn)
 {