Kalle Valo [off-list ref] writes:

quoted

+vdev_stop:
+	reinit_completion(&ar->vdev_setup_done);
+
+	ret = ath11k_wmi_vdev_stop(ar, vdev_id);
+	if (ret) {
+		ath11k_warn(ar->ab, "failed to stop monitor vdev %i after start failure: %d\n",
+			    vdev_id, ret);
+		return ret;
+	}
+
+	ret = ath11k_mac_vdev_setup_sync(ar);
+	if (ret)
+		ath11k_warn(ar->ab, "failed to synchronize setup for vdev %i stop: %d\n",
+			    vdev_id, ret);

I added return ret here for consistency..

quoted

+	return ret;

I don't thinks this is right, in an error path (vdev_stop label) we
return 0? I changed this to -EIO.

quoted

+static int ath11k_mac_monitor_vdev_stop(struct ath11k *ar)
+{
+	int ret;
+
+	lockdep_assert_held(&ar->conf_mutex);
+
+	reinit_completion(&ar->vdev_setup_done);
+
+	ret = ath11k_wmi_vdev_stop(ar, ar->monitor_vdev_id);
+	if (ret)
+		ath11k_warn(ar->ab, "failed to request monitor vdev %i stop: %d\n",
+			    ar->monitor_vdev_id, ret);
+
+	ret = ath11k_mac_vdev_setup_sync(ar);
+	if (ret)
+ ath11k_warn(ar->ab, "failed to synchronize monitor vdev %i stop:
%d\n",
+			    ar->monitor_vdev_id, ret);
+
+	ret = ath11k_wmi_vdev_down(ar, ar->monitor_vdev_id);
+	if (ret)
+		ath11k_warn(ar->ab, "failed to put down monitor vdev %i: %d\n",
+			    ar->monitor_vdev_id, ret);
+
+	ath11k_dbg(ar->ab, ATH11K_DBG_MAC, "mac monitor vdev %i stopped\n",
+		   ar->monitor_vdev_id);
+	return ret;
+}

I was not sure what's the idea of error path handling here, we print
warnings but still continue the normal execution. I changed this so that
we bail out in the first error and if everything goes well we return 0.

I found quite a few missing error checks, too many to list here but
fixed in the pending branch:

https://git.kernel.org/pub/scm/linux/kernel/git/kvalo/ath.git/commit/?h=pending&id=8b2f8d11422e7909ff02db456cda41728f621de4

https://git.kernel.org/pub/scm/linux/kernel/git/kvalo/ath.git/commit/?h=pending&id=5ff318be206b3d2a0bfdcfaf0ac52cc3b4ecdeae

Please double check, compile tested only.

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