From: "Paul E. McKenney" <paulmck@linux.ibm.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>,
Andrea Parri <andrea.parri@amarulasolutions.com>,
linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
Alan Stern <stern@rowland.harvard.edu>,
Will Deacon <will.deacon@arm.com>,
Boqun Feng <boqun.feng@gmail.com>,
Nicholas Piggin <npiggin@gmail.com>,
David Howells <dhowells@redhat.com>,
Jade Alglave <j.alglave@ucl.ac.uk>,
Luc Maranget <luc.maranget@inria.fr>,
Akira Yokosawa <akiyks@gmail.com>,
Daniel Lustig <dlustig@nvidia.com>
Subject: Re: [RFC PATCH] tools/memory-model: Remove (dep ; rfi) from ppo
Date: Tue, 26 Feb 2019 06:28:45 -0800 [thread overview]
Message-ID: <20190226142845.GK4072@linux.ibm.com> (raw)
In-Reply-To: <20190226134906.GG32494@hirez.programming.kicks-ass.net>
On Tue, Feb 26, 2019 at 02:49:06PM +0100, Peter Zijlstra wrote:
> On Tue, Feb 26, 2019 at 12:38:13PM +0100, Borislav Petkov wrote:
> > On Tue, Feb 26, 2019 at 12:30:08PM +0100, Peter Zijlstra wrote:
> > > When I used the argc variant, gcc-8 'works', but with s/argc/1/ it is
> > > still broken.
> >
> > As requested on IRC:
>
> What I asked was if you could get your GCC developer friends to have a
> look at this :-)
Yes, this all is a bit on the insane side from a kernel viewpoint.
But the paper you found does not impose this; it has instead been there
for about 20 years, back before C and C++ admitted to the existence
of concurrency. But of course compilers are getting more aggressive,
and yes, some of the problems show up in single-threaded code.
The usual response is "then cast the pointers to intptr_t!" but of
course that breaks type checking.
There is an effort to claw back the concurrency pieces, and I would
be happy to run the resulting paper past you guys.
I must confess to not being all that sympathetic to code that takes
advantage of happenstance stack-frame layout. Is there some reason
we need that?
Thanx, Paul
next prev parent reply other threads:[~2019-02-26 14:28 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-19 22:57 [RFC PATCH] tools/memory-model: Remove (dep ; rfi) from ppo Andrea Parri
2019-02-20 2:01 ` Paul E. McKenney
2019-02-20 9:26 ` Peter Zijlstra
2019-02-20 9:57 ` Will Deacon
2019-02-20 13:17 ` Andrea Parri
2019-02-20 13:14 ` Andrea Parri
2019-02-20 13:27 ` Peter Zijlstra
2019-02-22 11:21 ` Andrea Parri
2019-02-22 13:00 ` Peter Zijlstra
2019-02-25 17:55 ` Paul E. McKenney
2019-02-26 9:21 ` Peter Zijlstra
2019-02-26 9:30 ` Peter Zijlstra
2019-02-26 10:45 ` Peter Zijlstra
2019-02-26 11:21 ` Peter Zijlstra
2019-02-26 11:25 ` Peter Zijlstra
2019-02-26 11:30 ` Peter Zijlstra
2019-02-26 11:38 ` Borislav Petkov
2019-02-26 13:49 ` Peter Zijlstra
2019-02-26 14:28 ` Paul E. McKenney [this message]
2019-02-26 14:47 ` Peter Zijlstra
2019-02-26 15:39 ` Paul E. McKenney
2019-02-26 14:56 ` Akira Yokosawa
2019-02-26 15:04 ` Paul E. McKenney
2019-02-26 15:09 ` Akira Yokosawa
2019-02-26 15:04 ` Peter Zijlstra
2019-03-06 15:46 ` Akira Yokosawa
2019-03-06 16:58 ` Peter Zijlstra
2019-03-06 17:26 ` Paul E. McKenney
2019-03-06 17:24 ` Paul E. McKenney
2019-03-02 15:27 ` Akira Yokosawa
2019-03-04 16:09 ` Paul E. McKenney
2019-02-20 13:41 ` Will Deacon
2019-02-20 15:30 ` Alan Stern
2019-02-20 15:30 ` Alan Stern
2019-02-20 15:22 ` Alan Stern
2019-02-20 15:22 ` Alan Stern
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190226142845.GK4072@linux.ibm.com \
--to=paulmck@linux.ibm.com \
--cc=akiyks@gmail.com \
--cc=andrea.parri@amarulasolutions.com \
--cc=boqun.feng@gmail.com \
--cc=bp@alien8.de \
--cc=dhowells@redhat.com \
--cc=dlustig@nvidia.com \
--cc=j.alglave@ucl.ac.uk \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luc.maranget@inria.fr \
--cc=npiggin@gmail.com \
--cc=peterz@infradead.org \
--cc=stern@rowland.harvard.edu \
--cc=will.deacon@arm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.