From: <jeroen.de_wachter....@nokia.com> Date: Mon, 12 Dec 2016 14:29:08 +0100
> From: Jeroen De Wachter <jeroen.de_wachter....@nokia.com> > > Before, encx24j600_rx_packets did not update encx24j600_priv's next_packet > member when an error occurred during packet handling (either because the > packet's RSV header indicates an error or because the > encx24j600_receive_packet > method can't allocate an sk_buff). > > If the next_packet member is not updated, the ERXTAIL register will be set to > the same value it had before, which means the bad packet remains in the > component's memory and its RSV header will be read again when a new packet > arrives. If the RSV header indicates a bad packet or if sk_buff allocation > continues to fail, new packets will be stored in the component's memory until > that memory is full, after which packets will be dropped. > > The SETPKTDEC command is always executed though, so the encx24j600 hardware > has > an incorrect count of the packets in its memory. > > To prevent this, the next_packet member should always be updated, allowing the > packet to be skipped (either because it's bad, as indicated in its RSV header, > or because allocating an sk_buff failed). In the allocation failure case, this > does mean dropping a valid packet, but dropping the oldest packet to keep as > much memory as possible available for new packets seems preferable to keeping > old (but valid) packets around while dropping new ones. > > Signed-off-by: Jeroen De Wachter <jeroen.de_wachter....@nokia.com> Applied.
