diff --git a/sys/dev/mlx4/device.h b/sys/dev/mlx4/device.h
index 6fab35f3e50f..2095df7a700a 100644
--- a/sys/dev/mlx4/device.h
+++ b/sys/dev/mlx4/device.h
@@ -218,6 +218,23 @@ enum {
 	MLX4_DEV_CAP_CQ_FLAG_IO			= 1 <<  0
 };
 
+enum {
+	MLX4_QUERY_FUNC_FLAGS_BF_RES_QP	= 1LL << 0
+};
+
+/* bit enums for an 8-bit flags field indicating special use
+ * QPs which require special handling in qp_reserve_range.
+ * Currently, this only includes QPs used by the ETH interface,
+ * where we expect to use blueflame.  These QPs must not have
+ * bits 6 and 7 set in their qp number.
+ *
+ * This enum may use only bits 0..7.
+ */
+enum {
+	MLX4_RESERVE_ETH_BF_QP		= 1 << 7,
+};
+
+
 enum {
 	MLX4_DEV_CAP_64B_EQE_ENABLED	= 1LL << 0,
 	MLX4_DEV_CAP_64B_CQE_ENABLED	= 1LL << 1
@@ -533,6 +550,7 @@ struct mlx4_caps {
 	u32			max_basic_counters;
 	u32			max_extended_counters;
 	u8			def_counter_index[MLX4_MAX_PORTS + 1];
+	u8			alloc_res_qp_mask;
 };
 
 struct mlx4_buf_list {
diff --git a/sys/dev/mlx4/mlx4_core/fw.h b/sys/dev/mlx4/mlx4_core/fw.h
index 5649bc0771a3..748b2841d93d 100644
--- a/sys/dev/mlx4/mlx4_core/fw.h
+++ b/sys/dev/mlx4/mlx4_core/fw.h
@@ -145,6 +145,7 @@ struct mlx4_func_cap {
 	u8	physical_port;
 	u8	port_flags;
 	u8	def_counter_index;
+	u8	extra_flags;
 };
 
 struct mlx4_func {
diff --git a/sys/dev/mlx4/mlx4_core/mlx4_fw.c b/sys/dev/mlx4/mlx4_core/mlx4_fw.c
index 1a52c599022d..5d137d1637f4 100644
--- a/sys/dev/mlx4/mlx4_core/mlx4_fw.c
+++ b/sys/dev/mlx4/mlx4_core/mlx4_fw.c
@@ -265,10 +265,15 @@ int mlx4_QUERY_FUNC_CAP_wrapper(struct mlx4_dev *dev, int slave,
 #define QUERY_FUNC_CAP_MTT_QUOTA_OFFSET		0x64
 #define QUERY_FUNC_CAP_MCG_QUOTA_OFFSET		0x68
 
+#define QUERY_FUNC_CAP_EXTRA_FLAGS_OFFSET	0x6c
+
 #define QUERY_FUNC_CAP_FMR_FLAG			0x80
 #define QUERY_FUNC_CAP_FLAG_RDMA		0x40
 #define QUERY_FUNC_CAP_FLAG_ETH			0x80
 #define QUERY_FUNC_CAP_FLAG_QUOTAS		0x10
+#define QUERY_FUNC_CAP_FLAG_VALID_MAILBOX	0x04
+
+#define QUERY_FUNC_CAP_EXTRA_FLAGS_BF_QP_ALLOC_FLAG	(1UL << 31)
 
 /* when opcode modifier = 1 */
 #define QUERY_FUNC_CAP_PHYS_PORT_OFFSET		0x3
@@ -322,7 +327,7 @@ int mlx4_QUERY_FUNC_CAP_wrapper(struct mlx4_dev *dev, int slave,
 	} else if (vhcr->op_modifier == 0) {
 		/* enable rdma and ethernet interfaces, and new quota locations */
 		field = (QUERY_FUNC_CAP_FLAG_ETH | QUERY_FUNC_CAP_FLAG_RDMA |
-			 QUERY_FUNC_CAP_FLAG_QUOTAS);
+			 QUERY_FUNC_CAP_FLAG_QUOTAS | QUERY_FUNC_CAP_FLAG_VALID_MAILBOX);
 		MLX4_PUT(outbox->buf, field, QUERY_FUNC_CAP_FLAGS_OFFSET);
 
 		field = dev->caps.num_ports;
@@ -382,6 +387,8 @@ int mlx4_QUERY_FUNC_CAP_wrapper(struct mlx4_dev *dev, int slave,
 		MLX4_PUT(outbox->buf, size, QUERY_FUNC_CAP_MCG_QUOTA_OFFSET);
 		MLX4_PUT(outbox->buf, size, QUERY_FUNC_CAP_MCG_QUOTA_OFFSET_DEP);
 
+		size = QUERY_FUNC_CAP_EXTRA_FLAGS_BF_QP_ALLOC_FLAG;
+		MLX4_PUT(outbox->buf, size, QUERY_FUNC_CAP_EXTRA_FLAGS_OFFSET);
 	} else
 		err = -EINVAL;
 
@@ -474,6 +481,17 @@ int mlx4_QUERY_FUNC_CAP(struct mlx4_dev *dev, u32 gen_or_port,
 		MLX4_GET(size, outbox, QUERY_FUNC_CAP_RESERVED_EQ_OFFSET);
 		func_cap->reserved_eq = size & 0xFFFFFF;
 
+		func_cap->extra_flags = 0;
+
+		/* Mailbox data from 0x6c and onward should only be treated if
+		 * QUERY_FUNC_CAP_FLAG_VALID_MAILBOX is set in func_cap->flags
+		 */
+		if (func_cap->flags & QUERY_FUNC_CAP_FLAG_VALID_MAILBOX) {
+			MLX4_GET(size, outbox, QUERY_FUNC_CAP_EXTRA_FLAGS_OFFSET);
+			if (size & QUERY_FUNC_CAP_EXTRA_FLAGS_BF_QP_ALLOC_FLAG)
+				func_cap->extra_flags |= MLX4_QUERY_FUNC_FLAGS_BF_RES_QP;
+		}
+
 		goto out;
 	}
 
diff --git a/sys/dev/mlx4/mlx4_core/mlx4_main.c b/sys/dev/mlx4/mlx4_core/mlx4_main.c
index 7389194977e9..9bef78ac50cd 100644
--- a/sys/dev/mlx4/mlx4_core/mlx4_main.c
+++ b/sys/dev/mlx4/mlx4_core/mlx4_main.c
@@ -849,6 +849,11 @@ static int mlx4_dev_cap(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
 	if (!mlx4_is_slave(dev)) {
 		for (i = 0; i < dev->caps.num_ports; ++i)
 			dev->caps.def_counter_index[i] = i << 1;
+
+		dev->caps.alloc_res_qp_mask =
+			(dev->caps.bf_reg_size ? MLX4_RESERVE_ETH_BF_QP : 0);
+	} else {
+		dev->caps.alloc_res_qp_mask = 0;
 	}
 
 	return 0;
@@ -1114,6 +1119,10 @@ static int mlx4_slave_cap(struct mlx4_dev *dev)
 
 	slave_adjust_steering_mode(dev, &dev_cap, &hca_param);
 
+	if (func_cap.extra_flags & MLX4_QUERY_FUNC_FLAGS_BF_RES_QP &&
+	    dev->caps.bf_reg_size)
+		dev->caps.alloc_res_qp_mask |= MLX4_RESERVE_ETH_BF_QP;
+
 	return 0;
 
 err_mem:
diff --git a/sys/dev/mlx4/mlx4_core/mlx4_qp.c b/sys/dev/mlx4/mlx4_core/mlx4_qp.c
index 479771997a88..3b40b4563d16 100644
--- a/sys/dev/mlx4/mlx4_core/mlx4_qp.c
+++ b/sys/dev/mlx4/mlx4_core/mlx4_qp.c
@@ -242,6 +242,9 @@ int mlx4_qp_reserve_range(struct mlx4_dev *dev, int cnt, int align,
 	u64 out_param;
 	int err;
 
+	/* Turn off all unsupported QP allocation flags */
+	flags &= dev->caps.alloc_res_qp_mask;
+
 	if (mlx4_is_mfunc(dev)) {
 		set_param_l(&in_param, (((u32) flags) << 24) | (u32) cnt);
 		set_param_h(&in_param, align);
diff --git a/sys/dev/mlx4/mlx4_core/mlx4_resource_tracker.c b/sys/dev/mlx4/mlx4_core/mlx4_resource_tracker.c
index 821c6dbf1696..43edcac1bfc9 100644
--- a/sys/dev/mlx4/mlx4_core/mlx4_resource_tracker.c
+++ b/sys/dev/mlx4/mlx4_core/mlx4_resource_tracker.c
@@ -1544,7 +1544,10 @@ static int qp_alloc_res(struct mlx4_dev *dev, int slave, int op, int cmd,
 	switch (op) {
 	case RES_OP_RESERVE:
 		count = get_param_l(&in_param) & 0xffffff;
-		flags = get_param_l(&in_param) >> 24;
+		/* Turn off all unsupported QP allocation flags that the
+		 * slave tries to set.
+		 */
+		flags = (get_param_l(&in_param) >> 24) & dev->caps.alloc_res_qp_mask;
 		align = get_param_h(&in_param);
 		err = mlx4_grant_resource(dev, slave, RES_QP, count, 0);
 		if (err)