[ofa-general] [PATCHv2] IB/ipoib: S/G and HW checksum support

[Michael S. Tsirkin]

> Michael's proposal is a nice optimization for the direct host to host
> case.
> 
> However as soon as a gateway/router (B above) is added there is a
> serious gap in the integrity domains.  A hardware problem (or software
> bug) in B could undetectably corrupt the packet, but it would be
> delivered to C with a valid checksum.  Hence an undetected data
> corruption for the overall network path A<->C.

Note that B can implement data integrity measures (e.g. ECC) to protect
against this.

> Undetected data corruption is a very nasty word for the enterprise and
> designs must strive to remove opportunities for such problems.
> 
> Hence I agree with Roland's comment that the name should imply the
> serious risk that this option can introduce and it should clearly not be
> the default behavior.
> 
> Michael's idea of doing this in a manner so the unchecksum'ed packets
> are unroutable may also be reasonable.



-- 
MST