On 3/27/2019 8:35 PM, Aaro Koskinen wrote:

From: Aaro Koskinen <redacted>

We always program the maximum DMA buffer size into the receive descriptor,
although the allocated size may be less. E.g. with the default MTU size
we allocate only 1536 bytes. If somebody sends us a bigger frame, then
memory may get corrupted.

Fix by using exact buffer sizes.

Signed-off-by: Aaro Koskinen <redacted>

So, I'm seeing that the maximum allowed buffer size that can be
put in the descriptor changes between enhanced descriptors to
normal descriptors (8KB vs. 2KB right ?).

Shouldn't stmmac_main know about this limit before trying to init
descriptors ?

We do limit the MTU according to HW version but I would rather
prefer not having to need to calculate min() values in the
descriptor code and just use the value as is ...

Thanks,
Jose Miguel Abreu