Hi Alexander, On Tue, Jan 07, 2025 at 06:17:13PM +0100, Alexander Hölzl wrote: > On 1/7/25 14:48, Marc Kleine-Budde wrote: > > On 07.01.2025 14:32:17, Alexander Hölzl wrote: > > > The J1939 standard requires the transmission of messages of length 0. > > > For example the proprietary messages are specified with a data length > > > of 0 to 1785. The transmission of such messages was not possible. > > > Sending such a message resulted in no error being returned but no > > > corresponding can frame being generated. > > > > What does your patch do? Please describe it here. > > > > Marc > The patch enables the transmission of zero length J1939 messages. > In order to facilitate this two changes were necessary. > > First when the transmission of a new message is requested from userspace > the message is segmented in j1939_sk_send_loop. The segmentation did > account for zero length messages and terminated immediately without > queuing the corresponding skb. > > Second when selecting the next skb in j1939_session_skb_get_by_offset to > transmit for a session, it was not checked that there now might be a > zero length skb in the queue. > > Also as this is my first real patch I'm submitting please don't hesitate > to tell me if I'm doing something wrong. Please resend this patch with updated, more detailed, commit message. > > > Signed-off-by: Alexander Hölzl <alexander.hoelzl@xxxxxxx> Acked-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx> Thank you! -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
