[ofa-general] [PATCH] IPoIB UD 4K MTU support

[Roland Dreier]

 > Actually, I found a problem in IPoIB-CM here. Looks like most of HCAs do
 > support S/G numbers > 16. Then the other OS implementation could have
 > IPoIB link MTU = 64K -4 instead of current implementation 64K-16. It
 > could be a problem for this implementation to be in a mixed OS
 > evviornment. Just like my previous simple approach implementation for
 > IPoIB-UD, which is IPoIB link MTU = 4K - 48.

I don't think CM is quite the same issue as for 4K-4 MTU, as one could
easily imagine an implementation that allows an MTU of 128KB or 1MB or
whatever.  Also the CM protocol negotiates the receive size available,
so we shouldn't have the problems of getting a local length error.

 - R.