Re: [lwip-users] Corrupted ETH Rx Buffer in STM32H7 with TCP protocol

[Rogier Wolff]

On Tue, May 31, 2022 at 03:41:49PM +0200, Indan Zupancic wrote:
> This is probably because the ST driver releases the DMA buffers
> before you have handled the data. It tries to do zero copy, but does
> it wrong.

The other option is that the cache is corrupting things. You need to
properly flush the caches after the DMA-into-a-buffer and before
accessing the data. 

I didn't have exactly the same setup as you, but possibly the same
source of the problem. I spent quite a lot of time on that issue...

        Roger.

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