RE: [PATCH 3/3] sfc: selftest: fix struct packing

[David Laight <David.Laight@ACULAB.COM>]

...
> Duplicating the definition isn't the prettiest thing in the world; it'd
>  do for a quick fix if needed but I assume W=1 warnings aren't blocking
>  anyone, so maybe defer this one for now and I'll follow up soon with a
>  rewrite that fixes this more cleanly?  My idea is to drop the __packed
>  from the containing struct, make efx_begin_loopback() copy the layers
>  separately, and efx_loopback_rx_packet() similarly do something less
>  direct than casting the packet data to the struct.

Maybe you can get away with adding a 16bit pad before the ethernet
header so that the IP header is actually aligned.

(Then fight all the stuff that stops you doing a memcpy()
that runs into a second field of a structure.)

Failing that maybe a single shared copy of the misaligned
IP header.

I also suspect you could just add __packed to the two 32bit
address fields.
That would generate better code on systems that care.

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)