Re: [PATCH v3 net-next 3/5] net: fec: add rx_frame_size to support configurable RX length

[Andrew Lunn]

On Sat, Aug 23, 2025 at 02:01:08PM -0500, Shenwei Wang wrote:
> Add a new rx_frame_size member in the fec_enet_private structure to
> decouple frame size configuration from max_buf_size. This allows more
> precise control over RX frame length settings. It is particularly useful
> for Jumbo frame support because the RX frame size may possible larger than
> the allocated RX buffer.

Please could you extend that a little. What happens if the received
frame is bigger than the buffer? Does the hardware fragment it over
two buffers?

> 
> Configure TRUNC_FL (Frame Truncation Length) based on the RX buffer size.
> Frames exceeding this limit will be treated as error packets and dropped.

This bit confuses me. You want to allow rx_frame_size to be bigger
than the buffer size, but you also want to discard frames bigger than
the buffer size?

    Andrew

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