Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754099AbcLNR4A (ORCPT ); Wed, 14 Dec 2016 12:56:00 -0500 Received: from mx1.redhat.com ([209.132.183.28]:37606 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753566AbcLNRz7 (ORCPT ); Wed, 14 Dec 2016 12:55:59 -0500 Subject: Re: [PATCH] IBcore/CM: Issue DREQ when receiving REQ/REP for stale QP To: Hans Westgaard Ry , Sean Hefty , Hal Rosenstock , Matan Barak , Erez Shitrit , Bart Van Assche , Ira Weiny , Or Gerlitz , Hakon Bugge , Yuval Shaia , linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org References: <1477653269-27359-1-git-send-email-hans.westgaard.ry@oracle.com> From: Doug Ledford Message-ID: Date: Wed, 14 Dec 2016 12:55:41 -0500 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.5.0 MIME-Version: 1.0 In-Reply-To: <1477653269-27359-1-git-send-email-hans.westgaard.ry@oracle.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="c5Vu9d9vTBgf5X0rPpv011i7PnsoumBpd" X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Wed, 14 Dec 2016 17:55:57 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3748 Lines: 88 This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --c5Vu9d9vTBgf5X0rPpv011i7PnsoumBpd Content-Type: multipart/mixed; boundary="Wt9wuoMsfJftsxTlmu3qGPguoSJ7XwDFl"; protected-headers="v1" From: Doug Ledford To: Hans Westgaard Ry , Sean Hefty , Hal Rosenstock , Matan Barak , Erez Shitrit , Bart Van Assche , Ira Weiny , Or Gerlitz , Hakon Bugge , Yuval Shaia , linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org Message-ID: Subject: Re: [PATCH] IBcore/CM: Issue DREQ when receiving REQ/REP for stale QP References: <1477653269-27359-1-git-send-email-hans.westgaard.ry@oracle.com> In-Reply-To: <1477653269-27359-1-git-send-email-hans.westgaard.ry@oracle.com> --Wt9wuoMsfJftsxTlmu3qGPguoSJ7XwDFl Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 10/28/2016 7:14 AM, Hans Westgaard Ry wrote: > from "InfiBand Architecture Specifications Volume 1": >=20 > A QP is said to have a stale connection when only one side has > connection information. A stale connection may result if the remote C= M > had dropped the connection and sent a DREQ but the DREQ was never > received by the local CM. Alternatively the remote CM may have lost > all record of past connections because its node crashed and rebooted,= > while the local CM did not become aware of the remote node's reboot > and therefore did not clean up stale connections. >=20 > and: >=20 > A local CM may receive a REQ/REP for a stale connection. It shall > abort the connection issuing REJ to the REQ/REP. It shall then issue= > DREQ with "DREQ:remote QPN=E2=80=9D set to the remote QPN from the R= EQ/REP. >=20 > This patch solves a problem with reuse of QPN. Current codebase, that > is IPoIB, relies on a REAP-mechanism to do cleanup of the structures > in CM. A problem with this is the timeconstants governing this > mechanism; they are up to 768 seconds and the interface may look > inresponsive in that period. Issuing a DREQ (and receiving a DREP) > does the necessary cleanup and the interface comes up. >=20 > Signed-off-by: Hans Westgaard Ry > Reviewed-by: H=C3=A5kon Bugge Thanks, applied. --=20 Doug Ledford GPG Key ID: 0E572FDD --Wt9wuoMsfJftsxTlmu3qGPguoSJ7XwDFl-- --c5Vu9d9vTBgf5X0rPpv011i7PnsoumBpd Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQIcBAEBCAAGBQJYUYedAAoJELgmozMOVy/dK9gQAJ/dlupiLj2KHodUJnMUmjQq TOXRr7+WMDtelt9HXUZV52o4oOP6fRS9H17Cvdm32IehgVRPeH0sf4HuS5WhJO9T H7Tm2SwrAwRPbjZdk8FaW3loFgroRJQi3lOzPG77uYSPi3lkfjwTn9ZH6etEbFe8 ohc3/pcIunuvze+uSi0tEMGpoBuXL05kmxAaiSGzj7ELB0e6bYZKUeIwuCeEo4Pi +fPMi/bE/oRNq7mB2/hUXwfzi087W1BZcvyB/uet2DSfx67inkPfv+jeGrHLzl7X DKiiu3sU34Lp0uwLqJNysRmBjAWezDjmIXccijBr0flsdG0Qihba4SWroU9rRblS 5A8PTCFsf1lPmsDVP7eU4eCj91+Nqy9zJ205D1X/EzFZKCcibh66pbi4lDAJUTS5 ow+n/+fEgr58hbZKIE6VDrJJHfUCkJ8wsAQrLQhGacPvTi4P1PdBYYJsAgKiToaI LWhO4EgRZ0sLIcC9+TGf8u8dU2tG3gRJ8uKlF2dk8hS0I9zFWPaXaOQxpo9Y0oln v96zNObSdIrMjGdLt7oHfQsenV0jkSC6h662bjwdCDFyldGxE/lVBZafZO+SRP/b YV36rwXgXYN8jBXzuu+9vRI9nt4F9TfRw5XKHiYjOm96RN3GkSRBnSyd+X8yNDNy ge/LcByq3TYcfv3P9sOD =EBfF -----END PGP SIGNATURE----- --c5Vu9d9vTBgf5X0rPpv011i7PnsoumBpd--