diff --git a/sys/dev/mlx5/mlx5_ib/mlx5_ib_main.c b/sys/dev/mlx5/mlx5_ib/mlx5_ib_main.c
--- a/sys/dev/mlx5/mlx5_ib/mlx5_ib_main.c
+++ b/sys/dev/mlx5/mlx5_ib/mlx5_ib_main.c
@@ -681,7 +681,8 @@
 	props->device_cap_flags    = IB_DEVICE_CHANGE_PHY_PORT |
 		IB_DEVICE_PORT_ACTIVE_EVENT		|
 		IB_DEVICE_SYS_IMAGE_GUID		|
-		IB_DEVICE_RC_RNR_NAK_GEN;
+		IB_DEVICE_RC_RNR_NAK_GEN		|
+		IB_DEVICE_KNOWSEPOCH;
 
 	if (MLX5_CAP_GEN(mdev, pkv))
 		props->device_cap_flags |= IB_DEVICE_BAD_PKEY_CNTR;