Re: [PATCH] can: j1939: make j1939_session_activate() fail if device is no longer registered

[Oleksij Rempel <o.rempel@pengutronix.de>]

Hi,

On Tue, Dec 09, 2025 at 06:43:12PM +0900, Tetsuo Handa wrote:
> Ping?

Sorry for delay.

> On 2025/11/25 22:39, Tetsuo Handa wrote:
> > Should we also make j1939_sk_queue_activate_next_locked() and
> > j1939_xtp_rx_rts_session_new() not to emit bogus warning message?
> linux-next-20251208 has gotten a trace with
> j1939_sk_queue_activate_next_locked() and j1939_xtp_rx_rts_session_new().
> Do we want to make these functions not to emit bogus warning message?
> 
> > Is this error case rare enough to tolerate bogus warning message?

Good question. You are right, error messages do not reflect the reality.

May be something like this?

j1939_sk_queue_activate_next_locked(struct j1939_session *session)

	ret = j1939_session_activate(first);
	if (ret) {
		if (ret == -EAGAIN || ret == -EBUSY)
			netdev_warn_once(first->priv->ndev,
					 "%s: 0x%p: Identical session is already activated.\n",
					 __func__, first);
		else
			netdev_warn_once(first->priv->ndev,
					 "%s: 0x%p: Activation failed with err %i.\n",
					 __func__, first, ret);

		first->err = ret;
		goto activate_next;
	}


j1939_xtp_rx_rts_session_new(struct j1939_priv *priv, struct ...

	ret = j1939_session_activate(session);
	if (ret) {
		if (ret == -EAGAIN)
			netdev_alert(priv->ndev, "%s: 0x%p: concurrent session with same addr (%02x %02x) is already active.\n",
			     __func__, session, skcb.addr.sa, skcb.addr.da);
		else
			netdev_warn(priv->ndev, "%s: 0x%p: session activation failed: %i\n",
				    __func__, session, ret);

		j1939_session_put(session);
		return NULL;

This can be done in a separate patch later.

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