From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1753718AbcERRLR (ORCPT <rfc822;w@1wt.eu>);
	Wed, 18 May 2016 13:11:17 -0400
Received: from merlin.infradead.org ([205.233.59.134]:38360 "EHLO
	merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1752779AbcERRLQ (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Wed, 18 May 2016 13:11:16 -0400
Date: Wed, 18 May 2016 19:10:59 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Gilad Ben Yossef <giladb@ezchip.com>, Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Rik van Riel <riel@redhat.com>, Tejun Heo <tj@kernel.org>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Christoph Lameter <cl@linux.com>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Andy Lutomirski <luto@amacapital.net>,
        "H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v12 10/13] arch/x86: enable task isolation functionality
Message-ID: <20160518171059.GN3193@twins.programming.kicks-ass.net>
References: <1459877922-15512-1-git-send-email-cmetcalf@mellanox.com>
 <1459877922-15512-11-git-send-email-cmetcalf@mellanox.com>
 <20160518162359.GK3193@twins.programming.kicks-ass.net>
 <fcee25f1-9459-6947-dc30-9bbe7d200dfb@mellanox.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <fcee25f1-9459-6947-dc30-9bbe7d200dfb@mellanox.com>
User-Agent: Mutt/1.5.21 (2012-12-30)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Wed, May 18, 2016 at 12:35:40PM -0400, Chris Metcalf wrote:
> On 5/18/2016 12:23 PM, Peter Zijlstra wrote:

> >
> >That seems to miss a whole bunch of exceptions... what up?
> 
> We only need to do an explicit call in the case where the exception does NOT
> result in a signal, since a signal is something that will be really obvious to
> the application in any case.  So it's just stuff like handled page faults,
> handled bounds checks for x86, handled unaligned load/store for tilegx, etc.

Right; as per your earlier signal explanation. This seems somewhat
fragile to maintain though and really could use more clarification.