linux-kernel - Re: [PATCH v2 01/17] IB/Verbs: Implement new callback query

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 10 Apr 2015 14:24:26 -0400
From:	Doug Ledford <dledford@...hat.com>
To:	Jason Gunthorpe <jgunthorpe@...idianresearch.com>
Cc:	"ira.weiny" <ira.weiny@...el.com>,
	Michael Wang <yun.wang@...fitbricks.com>,
	Roland Dreier <roland@...nel.org>,
	Sean Hefty <sean.hefty@...el.com>, linux-rdma@...r.kernel.org,
	linux-kernel@...r.kernel.org, linux-nfs@...r.kernel.org,
	netdev@...r.kernel.org, Hal Rosenstock <hal.rosenstock@...il.com>,
	Tom Tucker <tom@...ngridcomputing.com>,
	Steve Wise <swise@...ngridcomputing.com>,
	Hoang-Nam Nguyen <hnguyen@...ibm.com>,
	Christoph Raisch <raisch@...ibm.com>,
	Mike Marciniszyn <infinipath@...el.com>,
	Eli Cohen <eli@...lanox.com>,
	Faisal Latif <faisal.latif@...el.com>,
	Upinder Malhi <umalhi@...co.com>,
	Trond Myklebust <trond.myklebust@...marydata.com>,
	"J. Bruce Fields" <bfields@...ldses.org>,
	"David S. Miller" <davem@...emloft.net>,
	PJ Waskiewicz <pj.waskiewicz@...idfire.com>,
	Tatyana Nikolova <Tatyana.E.Nikolova@...el.com>,
	Or Gerlitz <ogerlitz@...lanox.com>,
	Jack Morgenstein <jackm@....mellanox.co.il>,
	Haggai Eran <haggaie@...lanox.com>,
	Ilya Nelkenbaum <ilyan@...lanox.com>,
	Yann Droneaud <ydroneaud@...eya.com>,
	Bart Van Assche <bvanassche@....org>,
	Shachar Raindel <raindel@...lanox.com>,
	Sagi Grimberg <sagig@...lanox.com>,
	Devesh Sharma <devesh.sharma@...lex.com>,
	Matan Barak <matanb@...lanox.com>,
	Moni Shoua <monis@...lanox.com>, Jiri Kosina <jkosina@...e.cz>,
	Selvin Xavier <selvin.xavier@...lex.com>,
	Mitesh Ahuja <mitesh.ahuja@...lex.com>,
	Li RongQing <roy.qing.li@...il.com>,
	Rasmus Villemoes <linux@...musvillemoes.dk>,
	Alex Estrin <alex.estrin@...el.com>,
	Eric Dumazet <edumazet@...gle.com>,
	Erez Shitrit <erezsh@...lanox.com>,
	Tom Gundersen <teg@...m.no>,
	Chuck Lever <chuck.lever@...cle.com>
Subject: Re: [PATCH v2 01/17] IB/Verbs: Implement new callback
 query_transport() for each HW

On Fri, 2015-04-10 at 12:04 -0600, Jason Gunthorpe wrote:
> On Fri, Apr 10, 2015 at 01:38:38PM -0400, ira.weiny wrote:
>  
> Hiding meaning is to say 'only run on IB or OPA': WHY are we limited
> to those two?

For something else, I might agree with this.  But, for the specific case
of IPoIB, it's pretty fair.  IPoIB is more than just an ULP.  It's a
spec.  And it's very IB specific.  It will only work with OPA because
OPA is imitating IB.  To run it on another fabric, you would need more
than just to make it work.  If the new fabric doesn't have a broadcast
group, or has multicast registration like IB does, you need the
equivalent of IBTA, whatever that may be for this new fabric, buy in on
the pre-defined multicast groups and you might need firmware support in
the switches.

> We can see how this might work in future, lets say OPAv2 *requires* the
> 32 bit LID, for that case cap_ib_address = 0 cap_opa_address = 1. If
> we don't update IPoIB and it uses the tests from above then it
> immediately, and correctly, stops running on those OPAv2 devices.
> 
> Once patched to support cap_op_address then it will begin working
> again. That seems very sane..

It is very sane from an implementation standpoint, but from the larger
interoperability standpoint, you need that spec to be extended to the
new fabric simultaneously.


-- 
Doug Ledford <dledford@...hat.com>
              GPG KeyID: 0E572FDD



Download attachment "signature.asc" of type "application/pgp-signature" (820 bytes)