Re: [lwip-users] Windows 7 Startup crashes LwIP and Free RTOS

[Simon Goldschmidt]

Marco Jakobs wrote:
> Question one:
> What is the behaviour of LwIP in that case, if there are still some 
> frames of the packet in the EMAC buffers but some other frames are 
> missing due to the EMAC threw them away because of an overflow?

That's rather a driver question, not an lwIP question: the driver should make 
sure that it only delivers complete packets to lwIP. I.e. if some parts of the 
packet are missing due to the MAC trying to split it to multiple buffers but 
running out of buffers half way through, the driver should throw away the 
partly received packet.

However, *if* the driver passes in the packet, some part of the code should 
detect an invalid packet and drop it. Which part detects that depends on where 
the packet is cut off (i.e. are the headers included at all, is the checksum 
correct/incorrect, etc.). While that code is there, it's always better to drop 
such packets as soon as possible, of course.

> Question two:
> Is there any action needed if the EMAC sets the receive overflow bit?

Can't help you with that... or the other hardware-related questions...

Simon
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