Re: [PATCH] IB/ipoib: move back the IB LL address into the hard header

[Paolo Abeni <pabeni-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

On Tue, 2016-10-11 at 11:42 -0600, Jason Gunthorpe wrote:
> On Tue, Oct 11, 2016 at 07:37:32PM +0200, Paolo Abeni wrote:
> > On Tue, 2016-10-11 at 11:32 -0600, Jason Gunthorpe wrote:
> > > On Tue, Oct 11, 2016 at 07:15:44PM +0200, Paolo Abeni wrote:
> > > 
> > > > Also the connected mode maximum mtu is reduced by 16 bytes to
> > > > cope with the increased hard header len.
> > > 
> > > Changing the MTU is going to cause annoying interop problems, can you
> > > avoid this?
> > 
> > I don't like changing the maximum MTU value, too, but I was unable to
> > find an alternative solution. The PMTU detection should protect against
> > such issues.
> 
> It is more that PMTU, we have instructed all users that is the MTU
> number needed to enable CM mode, so it appears in documentation,
> scripts, etc.

AFAICS the max mtu is already underlying h/w dependent, how does such
differences are currently coped by ? (I'm sorry I lack some/a lot of IB
back-ground)

--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html