From: Jeff Garzik <[EMAIL PROTECTED]> Date: Wed, 21 Nov 2007 19:17:40 -0500
> YOSHIFUJI Hideaki / 吉藤英明 wrote: > > In article <[EMAIL PROTECTED]> (at Wed, 21 Nov 2007 07:45:32 -0500), Jeff > > Garzik <[EMAIL PROTECTED]> says: > > > >> SO_NO_CHECK support for IPv6 appeared to be missing. This is presented, > >> based on a reading of net/ipv4/udp.c. > > > > Disagree. UDP checksum is mandatory in IPv6. > > Ah, you mean that I need to turn off UDP checksum on receive end as well > in IPv6... true. > > For those interested, I am dealing with a UDP app that already does very > strong checksumming and encryption, so additional software checksumming > at the lower layers is quite simply a waste of CPU cycles. Hardware > checksumming is fine, as long as its "free." Regardless of whatever verifications your application is doing on the data, it is not checksumming the ports and that's what the pseudo-header is helping with. You cannot disable checksums in ipv6/UDP, they are not optional and with %99.9999999 of cards doing the checksum in hardware, and even if we do have to compute it it's free during the copy during recvmsg(). - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
