From mboxrd@z Thu Jan 1 00:00:00 1970 From: Doug Ledford Subject: Re: [PATCH] IB/ipoib: Change To max_cm_mtu when changing mode to connected Date: Mon, 08 Jun 2015 17:27:45 -0400 Message-ID: <1433798865.90034.5.camel@redhat.com> References: <1433673371-5355-1-git-send-email-erezsh@mellanox.com> <20150608164224.GA2499@obsidianresearch.com> <1433797482.90034.2.camel@redhat.com> <20150608210751.GA13388@obsidianresearch.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-0QOxsIgxeTYWN3mGZFwF" Return-path: In-Reply-To: <20150608210751.GA13388-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jason Gunthorpe Cc: Erez Shitrit , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, ogerlitz-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org, vlad-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org, ELi Cohen List-Id: linux-rdma@vger.kernel.org --=-0QOxsIgxeTYWN3mGZFwF Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, 2015-06-08 at 15:07 -0600, Jason Gunthorpe wrote: > On Mon, Jun 08, 2015 at 05:04:42PM -0400, Doug Ledford wrote: > > On Mon, 2015-06-08 at 10:42 -0600, Jason Gunthorpe wrote: > > > On Sun, Jun 07, 2015 at 01:36:11PM +0300, Erez Shitrit wrote: > > > >=20 > > > > When switching between modes (datagram / connected) change the MTU > > > > accordingly. > > > > datagram mode up to 4K, connected mode up to (64K - 0x10). > > >=20 > > > Is this a bug fix (describe the user visible impact)? Should it go to > > > -stable? Add a Fixes: line? > >=20 > > I'm not sure I would call it a bug. Setting the MTU to max > > automatically is a policy decision more than anything else. Currently, > > you have to enable connected mode, then set the MTU. Both initscripts > > and NetworkManager do this for you on Red Hat, so the user sees no > > difference here. I can't speak to other OSes. I'm OK with setting > > connected mode MTU to max by default once we get the scatter/gather > > support for IPoIB added. >=20 > I was thinking about the other direction, what happens when you turn > connected mode off? It drops back down to IB MTU - 4. --=20 Doug Ledford GPG KeyID: 0E572FDD --=-0QOxsIgxeTYWN3mGZFwF Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAABCAAGBQJVdgjRAAoJELgmozMOVy/dN/gP/Ayng5CYE/Ch2YuxPpr9zYzt ffUxeiTgitwPnKrkNtH8rMRCMl/satd94ZsnOVcKNJ50n9uJp+/5Bm/qZLFUBOMK X/OrDeTaAjJnJ4nKtEGGgbQUxbT10n8HJdCB8SVwx6c8xrz9eiThXE37VwUctQUG vA/WSLZ04BPzFsiJKg+sMCeivUNUZrFP8RoVSjof7lrCRLq03DU+eZyDh+O0iC82 oOCd3VZWIUJjdZcyjc68ZXnsPOvJzygdWSsBrn9n20LP2iiE6QcNjanbmazCNaOh 7SJCg9Hpf8RaqkDV0eodlkaZY7ZJzr42uwnwGoIyUw8gxa+fqY7tR4HeWRDGmYL9 D+AEw6VcpUp4L3HvuidCrV1MNh98LwvtYCcljj5huMhmifKkGH3n4egz/riijS/C Ewrt/ZsdqiZofSnhLTayqfakGiLEQBFP9LwdpFAAWY5tx+992xlDhGQLqu9o9inE PDzXW5otxeT+OIO4l4sf2NeMF9E793mKPFif8r7CsxXGo0oN8GGsOO0TARtZqCCZ ocIf7TKCTH4J7ePviSLkNb3Vox4MCQoqo7M1iQxq3hJNnvFqkgeT6jrhXlQ8mZO3 2zgChAI/AadmRh6tj5AmgzttiTRRdef6aU/tm2G5OokfUXVRT+ASeM3KdLhG2ZaC j9zVZvAEnC/nWjth6HRk =BtLE -----END PGP SIGNATURE----- --=-0QOxsIgxeTYWN3mGZFwF-- -- 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