On Thu, Jul 20, 2006 at 01:32:42PM -0500, Ian Remmler wrote: > Hi, > > I'm having a problem with the ibm_emac driver for the built in > gigabit ethernet on the 440gx. I was hoping someone could shed > some light or at least point me in the right direction. > > I'm using a GMS P502 board runing 2.4.27-pre3 (from GMS). The > problem we are having is this: when we push data over the emac > interface (eth0 and eth1 both show the problem), we sporadically > get a "MAL: Rx descriptor error..." from mal_rxde in > ibm_ocp_mal.c. > > Occasionally, the interface will "freeze up" for a few seconds. > An ifconfig down/up will bring it back, but from then on it will > freeze up again right away. > > It looks to me like this error indicates that we're out of RX > buffers, but I don't how we would be running out. I'm no kernel > or networking expert, but I thought the TCP stack would take > care of throttling itself to prevent that sort of thing. I > would appreciate any help.
No idea what GMS is, but they seem to use old buggy EMAC driver. You can use kernel.org's 2.6 or 2.4.31 backport at http://kernel.ebshome.net/ As a side note, TCP cannot throttle _all_ Rx traffic, think for example of a fast box sending a lot of small UDP packets to the 440gx. -- Eugene