Re: mue(4) patch

[Rin Okuyama <rokuyama%rk.phys.keio.ac.jp@localhost>]

Hi,

On 2018/12/03 23:21, Robert Swindells wrote:
> I have put a patch to the mue(4) driver on ftp.n.o that adds support for
> checksum offloading. It seems to be working fine but maybe could use
> some more testing before I commit it.
>
> <https://ftp.NetBSD.org/pub/NetBSD/misc/rjs/if_mue.patch.gz>
>
> Copied to port-arm as the RPi B3+ uses this driver.
>
> Robert Swindells

Thank you for working on this! I revised your patch as follows:

http://www.netbsd.org/~rin/if_mue_20181204.patch

(1) We need to check bits 30 and 31 of rx_cmd_a, which indicate
    checksum error detected by H/W for L4 and L3, respectively.
    Otherwise, broken packets bypass any checksumming.

(2) Mask csum by ifp->if_csum_flags_rx in mue_rxeof() for safety.

(3) Some style changes.

I've tested the patch with Z-TEK ZE582 (LAN7500). It works fine
as far as I can see, although no checksum errors were detected
during test.

Does anyone know a convenient way to generate packets with wrong
L3/L4 checksum fields?

Thanks,
rin