diff --git a/sys/compat/linuxkpi/common/include/linux/ieee80211.h b/sys/compat/linuxkpi/common/include/linux/ieee80211.h
--- a/sys/compat/linuxkpi/common/include/linux/ieee80211.h
+++ b/sys/compat/linuxkpi/common/include/linux/ieee80211.h
@@ -115,7 +115,8 @@
 #define	IEEE80211_TKIP_ICV_LEN			4
 #define	IEEE80211_TKIP_IV_LEN			8	/* WEP + KID + EXT */
 
-#define	IEEE80211_VHT_EXT_NSS_BW_CAPABLE	(1 << 13)	/* assigned to tx_highest */
+/* 802.11-2016, 9.4.2.158.3 Supported VHT-MCS and NSS Set field. */
+#define	IEEE80211_VHT_EXT_NSS_BW_CAPABLE	(1 << 13)	/* part of tx_highest */
 
 #define	IEEE80211_VHT_MAX_AMPDU_1024K		7	/* 9.4.2.56.3 A-MPDU Parameters field, Table 9-163 */
 
diff --git a/sys/compat/linuxkpi/common/include/net/cfg80211.h b/sys/compat/linuxkpi/common/include/net/cfg80211.h
--- a/sys/compat/linuxkpi/common/include/net/cfg80211.h
+++ b/sys/compat/linuxkpi/common/include/net/cfg80211.h
@@ -236,7 +236,8 @@
 #define	IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK	\
 	(7 << IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_SHIFT)	/* IEEE80211_VHTCAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK */
 
-#define	IEEE80211_VHT_CAP_EXT_NSS_BW_MASK	0xc0000000
+#define	IEEE80211_VHT_CAP_EXT_NSS_BW_MASK	IEEE80211_VHTCAP_EXT_NSS_BW
+#define	IEEE80211_VHT_CAP_EXT_NSS_BW_SHIFT	IEEE80211_VHTCAP_EXT_NSS_BW_S
 
 struct ieee80211_sta_vht_cap {
 		/* TODO FIXME */
diff --git a/sys/net80211/ieee80211.h b/sys/net80211/ieee80211.h
--- a/sys/net80211/ieee80211.h
+++ b/sys/net80211/ieee80211.h
@@ -1045,6 +1045,10 @@
 #define	IEEE80211_VHTCAP_TX_ANTENNA_PATTERN	0x20000000
 #define	IEEE80211_VHTCAP_TX_ANTENNA_PATTERN_S	29
 
+/* 802.11-2016, 9.4.2.158.2 VHT Capabilities Information field. */
+#define	IEEE80211_VHTCAP_EXT_NSS_BW		0xc0000000
+#define	IEEE80211_VHTCAP_EXT_NSS_BW_S		30
+
 /*
  * XXX TODO: add the rest of the bits
  */