> Another possible cause (I have seen this) is that after the ARP entry expired, > and the client sends the pbuf chained, got queued in ARP layer, an ARP request > is sent. As soon the polling thread gets the ARP REPLY, it then updates the > table and try to send the queued data (in the thread itself). > The problem was, my low_level_output was not protected, hence the chances are > there that both tcpip thread (sending a TCP packet)and the polling thread access > low_level_output simulataneously and corrupted the index of my Ethernet buffer > descriptor. The TCP was retransmitted as it should, but the UDP data was lost, hence the echo stopped.
I guess this is fixed with lwIP 1.3.0 (if you adopt your drivers): The ARP layer is now called from within the tcpip_thread by setting netif->input to ethernet_input() instead of ip_input(). Resultingly, your driver should not call the ARP functions directly in your ethernetif_input function. This was a design error in lwIP multithreading. Simon. _______________________________________________ lwip-users mailing list lwip-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/lwip-users
