struct netdevsim *ns = cb_priv;
        struct bpf_prog *oldprog;
 
-       if (type != TC_SETUP_CLSBPF ||
-           !tc_can_offload(ns->netdev) ||
-           cls_bpf->common.protocol != htons(ETH_P_ALL) ||
-           cls_bpf->common.chain_index)
+       if (type != TC_SETUP_CLSBPF) {
+               NSIM_EA(cls_bpf->common.extack,
+                       "only offload of BPF classifiers supported");
                return -EOPNOTSUPP;
+       }
+
+       if (!tc_can_offload_extack(ns->netdev, cls_bpf->common.extack))
+               return -EOPNOTSUPP;
+
+       if (cls_bpf->common.protocol != htons(ETH_P_ALL)) {
+               NSIM_EA(cls_bpf->common.extack,
+                       "only ETH_P_ALL supported as filter protocol");
+               return -EOPNOTSUPP;
+       }
 
-       if (!ns->bpf_tc_accept)
+       if (cls_bpf->common.chain_index)
                return -EOPNOTSUPP;
+
+       if (!ns->bpf_tc_accept) {
+               NSIM_EA(cls_bpf->common.extack,
+                       "netdevsim configured to reject BPF TC offload");
+               return -EOPNOTSUPP;
+       }
        /* Note: progs without skip_sw will probably not be dev bound */
-       if (prog && !prog->aux->offload && !ns->bpf_tc_non_bound_accept)
+       if (prog && !prog->aux->offload && !ns->bpf_tc_non_bound_accept) {
+               NSIM_EA(cls_bpf->common.extack,
+                       "netdevsim configured to reject unbound programs");
                return -EOPNOTSUPP;
+       }
 
        if (cls_bpf->command != TC_CLSBPF_OFFLOAD)
                return -EOPNOTSUPP;
                oldprog = NULL;
                if (!cls_bpf->prog)
                        return 0;
-               if (ns->bpf_offloaded)
+               if (ns->bpf_offloaded) {
+                       NSIM_EA(cls_bpf->common.extack,
+                               "driver and netdev offload states mismatch");
                        return -EBUSY;
+               }
        }
 
        return nsim_bpf_offload(ns, cls_bpf->prog, oldprog);