Date: Wed, 14 Jul 2010 18:31:07 -0400
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Ingo Molnar <mingo@elte.hu>, LKML <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Steven Rostedt <rostedt@rostedt.homelinux.com>,
        Thomas Gleixner <tglx@linutronix.de>, Christoph Hellwig <hch@lst.de>,
        Li Zefan <lizf@cn.fujitsu.com>, Lai Jiangshan <laijs@cn.fujitsu.com>,
        Johannes Berg <johannes.berg@intel.com>,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Arnaldo Carvalho de Melo <acme@infradead.org>,
        Tom Zanussi <tzanussi@gmail.com>,
        KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
        Andi Kleen <andi@firstfloor.org>, "H. Peter Anvin" <hpa@zytor.com>,
        Jeremy Fitzhardinge <jeremy@goop.org>,
        "Frank Ch. Eigler" <fche@redhat.com>, Tejun Heo <htejun@gmail.com>
Subject: Re: [patch 1/2] x86_64 page fault NMI-safe
Message-ID: <20100714223107.GA2350@Krystal>
References: <20100714154923.947138065@efficios.com> <20100714155804.049012415@efficios.com> <AANLkTiml2uwYqQayTKjMN2gI3LnjVFpwxXkv8GN3McEE@mail.gmail.com> <20100714170617.GB4955@Krystal> <AANLkTinLB3gQNKFk9QRfBS8YEfxL3qxZDFw7vWHDOnmL@mail.gmail.com> <20100714184642.GA9728@elte.hu> <AANLkTil2r3sUcoCC_ktp3TV2JNTSMxbpke8yJMx_8lmm@mail.gmail.com> <20100714193652.GA13630@nowhere> <AANLkTilD4aYej_36lOCEvMNCdYc4jBIupi5-77oD9vD2@mail.gmail.com> <20100714221418.GA14533@nowhere>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20100714221418.GA14533@nowhere>
User-Agent: Mutt/1.5.18 (2008-05-17)
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1080
Lines: 32

* Frederic Weisbecker (fweisbec@gmail.com) wrote:
> On Wed, Jul 14, 2010 at 12:54:19PM -0700, Linus Torvalds wrote:
> > On Wed, Jul 14, 2010 at 12:36 PM, Frederic Weisbecker
> > <fweisbec@gmail.com> wrote:
> > >
> > > There is also the fact we need to handle the lost NMI, by defering its
> > > treatment or so. That adds even more complexity.
> > 
> > I don't think your read my proposal very deeply. It already handles
> > them by taking a fault on the iret of the first one (that's why we
> > point to the stack frame - so that we can corrupt it and force a
> > fault).
> 
> 
> Ah right, I missed this part.

Hrm, Frederic, I hate to ask that but.. what are you doing with those percpu 8k
data structures exactly ? :)

Mathieu


-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/