[lwip-users] lwIP example for Luminary Micro LM39B90 MCU - debug help

[Tn]

Hello everyone,

Being a bit displeased by very hairy official lwIP demo for Luminary
Micro LM3S9B90, I decided to create a template project for lwIP on
FreeRTOS (very popular platform) for newbies to easily start developing
using netconn api.

I almost got it working, but I can't remove a very annoyng bug. I can
start only ~150-250 connections during program runtime. 

I use tcpip_thread, ethernet interrupt thread woken up from ISR to
call stellarisif_interrupt() pushing data into the stack. Ethernet
ISR priority is set to configMAX_SYSCALL_INTERRUPT_PRIORITY
(issue specific for Cortex-M3).

The "application task" is simple:

while(1) {
        UARTprintf("Listening... ");
        connClient = netconn_accept(connList);
        if( connClient != NULL ) {
                UARTprintf("accepted\n");
                netconn_delete(connClient);
                UARTprintf("deleted\n");
        } else {
                UARTprintf("invalid!\n");
        }
}

After 150-250 iterations (depending on compiled options, stack
spaces, etc), MCU crashes in tcpip_thread. I tried to double, triple,
quadruple stack space, but to no effect. This is 100% reproductible,
it crashes always the same way (ex. after 165 iterations). Exact
iteration depends on compile options.

I search for more experienced developer to help me debug this.
Entire project code will be donated for lwIP project for everyone to
benefit. I've seen that many people search for a complete, clean, and
easy to analyze example for lwIP under FreeRTOS.

I'll provide full code for request.

Thanks,
TN