Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757127Ab2EVClG (ORCPT ); Mon, 21 May 2012 22:41:06 -0400 Received: from relay3.sgi.com ([192.48.152.1]:34036 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755626Ab2EVClE (ORCPT ); Mon, 21 May 2012 22:41:04 -0400 Date: Mon, 21 May 2012 21:41:01 -0500 From: Dimitri Sivanich To: Suresh Siddha Cc: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Yinghai Lu , Naga Chumbalkar , Jacob Pan , linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86: check for valid irq_cfg pointer in smp_irq_move_cleanup_interrupt Message-ID: <20120522024101.GA30298@sgi.com> References: <20120521164959.GE16454@sgi.com> <1337634353.1997.144.camel@sbsiddha-desk.sc.intel.com> <20120521210901.GA25326@sgi.com> <1337634639.1997.148.camel@sbsiddha-desk.sc.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1337634639.1997.148.camel@sbsiddha-desk.sc.intel.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1319 Lines: 34 On Mon, May 21, 2012 at 02:10:39PM -0700, Suresh Siddha wrote: > On Mon, 2012-05-21 at 16:09 -0500, Dimitri Sivanich wrote: > > On Mon, May 21, 2012 at 02:05:53PM -0700, Suresh Siddha wrote: > > > On Mon, 2012-05-21 at 11:49 -0500, Dimitri Sivanich wrote: > > > > The smp_irq_move_cleanup_interrupt routine should be checking for a valid > > > > irq_cfg pointer prior to accessing it. It also seems that this should be > > > > done after taking the desc lock. > > > > > > I think these changes are correct. Did you see any crashes during module > > > unload etc? > > > > Yes, we have seen these on occasion during boot. > > During boot or shutdown? > Early on in boot, on rare occasions. Easiest to reproduce doing module repeated module loads/unloads. > Review of the code shows that this can trigger during module unload > which can call destroy_irq() etc and can trigger the crash if there is a > parallel irq migration related cleanup. > > Unsuccessful module loads can also call destroy_irq() but I doubt that > is what happening here. > > thanks, > suresh > -- 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/