Index: head/sys/dev/sfxge/common/ef10_nic.c
===================================================================
--- head/sys/dev/sfxge/common/ef10_nic.c
+++ head/sys/dev/sfxge/common/ef10_nic.c
@@ -1321,6 +1321,16 @@
 		 */
 		encp->enc_rx_scale_l4_hash_supported = B_TRUE;
 	}
+	/* Check if the firmware supports "FLAG" and "MARK" filter actions */
+	if (CAP_FLAGS2(req, FILTER_ACTION_FLAG))
+		encp->enc_filter_action_flag_supported = B_TRUE;
+	else
+		encp->enc_filter_action_flag_supported = B_FALSE;
+
+	if (CAP_FLAGS2(req, FILTER_ACTION_MARK))
+		encp->enc_filter_action_mark_supported = B_TRUE;
+	else
+		encp->enc_filter_action_mark_supported = B_FALSE;
 
 #undef CAP_FLAGS1
 #undef CAP_FLAGS2
Index: head/sys/dev/sfxge/common/efx.h
===================================================================
--- head/sys/dev/sfxge/common/efx.h
+++ head/sys/dev/sfxge/common/efx.h
@@ -1321,6 +1321,9 @@
 	/* Firmware support for extended MAC_STATS buffer */
 	uint32_t		enc_mac_stats_nstats;
 	boolean_t		enc_fec_counters;
+	/* Firmware support for "FLAG" and "MARK" filter actions */
+	boolean_t		enc_filter_action_flag_supported;
+	boolean_t		enc_filter_action_mark_supported;
 } efx_nic_cfg_t;
 
 #define	EFX_PCI_FUNCTION_IS_PF(_encp)	((_encp)->enc_vf == 0xffff)
Index: head/sys/dev/sfxge/common/siena_nic.c
===================================================================
--- head/sys/dev/sfxge/common/siena_nic.c
+++ head/sys/dev/sfxge/common/siena_nic.c
@@ -201,6 +201,9 @@
 
 	encp->enc_mac_stats_nstats = MC_CMD_MAC_NSTATS;
 
+	encp->enc_filter_action_flag_supported = B_FALSE;
+	encp->enc_filter_action_mark_supported = B_FALSE;
+
 	return (0);
 
 fail2: