Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753966Ab3JRLzD (ORCPT ); Fri, 18 Oct 2013 07:55:03 -0400 Received: from e9.ny.us.ibm.com ([32.97.182.139]:49795 "EHLO e9.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753902Ab3JRLy6 (ORCPT ); Fri, 18 Oct 2013 07:54:58 -0400 Date: Fri, 18 Oct 2013 04:54:51 -0700 From: "Paul E. McKenney" To: Steven Rostedt Cc: Frederic Weisbecker , LKML , Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , Andrew Morton , Peter Zijlstra , "x86@kernel.org" , "Wang, Xiaoming" , "Li, Zhuangzhi" , "Liu, Chuansheng" Subject: Re: [PATCH] x86: Remove WARN_ON(in_nmi()) from vmalloc_fault Message-ID: <20131018115451.GM31306@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <20131015163906.342d8ffa@gandalf.local.home> <20131016114036.GB12773@localhost.localdomain> <20131016084518.44eaf61a@gandalf.local.home> <20131016130856.GE12773@localhost.localdomain> <20131016193632.GH4553@linux.vnet.ibm.com> <20131016155730.7fd55ac5@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131016155730.7fd55ac5@gandalf.local.home> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13101811-7182-0000-0000-000008CB0F28 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 965 Lines: 30 On Wed, Oct 16, 2013 at 03:57:30PM -0400, Steven Rostedt wrote: > On Wed, 16 Oct 2013 12:36:32 -0700 > "Paul E. McKenney" wrote: > > > > > Ah but we have an in_interrupt() check in context_tracking_user_enter() that protects > > > us against that. > > > > Here you are relying on the exception being treated as an interrupt, > > correct? > > I don't think so. It's relying on nmi_enter() also makes in_interrupt() > return true. Got it, never mind! Thanx, Paul > Like I said before. An NMI interrupting userspace should be no > different than an interrupt interrupting userspace. They both can > trigger vmalloc faults, and we should be able to deal with it. > > -- Steve > -- 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/