I put a version of STP based on the 2.4.x zerocopy TCP patches
The diff can be found from
This removes the need for CONFIG_STP_DIRECT completely, and
thus makes the code a lot prettier. Also the STP-accelerated
acenic driver has been split into two parts, acenic.c and acenic_egast.c
(and as can be seen from a diff drivers/net/acenic.c
net/stp/drivers/acenic/acenic.c the changes are quite small now)
The firmware included is the one that works on 512k boards.
A small caveat, I have seen the acenic driver on the receiver
lock-up a few times with this version (this also has happened with the
non-STP zerocopy acenic driver, so there's still something funny
Technically it should work with a kernel without the zero-copy patches
too, although I haven't tested this...