linux-kernel - Re: [PATCH RFC tools/memory-model] Add s390.{cfg,cat}

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]

Message-Id: <20180328142004.GR3675@linux.vnet.ibm.com>
Date:   Wed, 28 Mar 2018 07:20:04 -0700
From:   "Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     schwidefsky@...ibm.com, borntraeger@...ibm.com,
        linux-kernel@...r.kernel.org, linux-arch@...r.kernel.org,
        stern@...land.harvard.edu, parri.andrea@...il.com,
        will.deacon@....com, boqun.feng@...il.com, npiggin@...il.com,
        dhowells@...hat.com, j.alglave@....ac.uk, luc.maranget@...ia.fr,
        akiyks@...il.com
Subject: Re: [PATCH RFC tools/memory-model] Add s390.{cfg,cat}

On Wed, Mar 28, 2018 at 03:48:13PM +0200, Peter Zijlstra wrote:
> On Wed, Mar 28, 2018 at 06:42:32AM -0700, Paul E. McKenney wrote:
> > Hello!
> > 
> > The prototype patch shown below provides files required to allow herd7 to
> > evaluate C-language litmus tests for the multicopy-atomic TSO ordering
> > provided by s390.  
> 
> There really isn't anything s390 specific here is there? That is, would
> this not equally work for x86 and sparc, both of which are similarly TSO
> ?

As I understand it, there is a difference.  The difference from TSO
systems such as x86 is that s390 is multicopy atomic as well as TSO.
In contrast, x86 is TSO as well as other-multicopy-atomic.  I must defer
to Martin and Christian for details -- this should be interpreted as a
feeble first attempt on my part, not any sort of IBM-approved definition
of s390.  ;-)

> Given that, should this not be called TSO instead of s390 ?

I agree completely with a single tso.cfg, TSO.cfg, or whatever name,
as opposed to a bunch of identical files for x86, SPARC, ...

							Thanx, Paul