Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752255AbZG1AOm (ORCPT ); Mon, 27 Jul 2009 20:14:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751949AbZG1AOl (ORCPT ); Mon, 27 Jul 2009 20:14:41 -0400 Received: from smtp-out.google.com ([216.239.33.17]:60208 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751159AbZG1AOl (ORCPT ); Mon, 27 Jul 2009 20:14:41 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=date:from:x-x-sender:to:cc:subject:in-reply-to:message-id: references:user-agent:mime-version:content-type:x-system-of-record; b=DXx5b11UwQ4SXiLliLCS0QUcEWN6CUyhHo3jQpI+D/x2qRpWbsskeelZ7kBLIvJl9 5r//8JIRPYqAgplxiZR6Q== Date: Mon, 27 Jul 2009 17:14:32 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: KAMEZAWA Hiroyuki cc: Andrew Morton , Lee Schermerhorn , KOSAKI Motohiro , miaox@cn.fujitsu.com, Ingo Molnar , Peter Zijlstra , Christoph Lameter , Paul Menage , Nick Piggin , y-goto@jp.fujitsu.com, Pekka Enberg , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [BUG] set_mempolicy(MPOL_INTERLEAV) cause kernel panic In-Reply-To: <20090728085810.f7ae678a.kamezawa.hiroyu@jp.fujitsu.com> Message-ID: References: <20090715182320.39B5.A69D9226@jp.fujitsu.com> <1247679064.4089.26.camel@useless.americas.hpqcorp.net> <20090724160936.a3b8ad29.akpm@linux-foundation.org> <337c5d83954b38b14a17f0adf4d357d8.squirrel@webmail-b.css.fujitsu.com> <5bb65c0e4c6828b1331d33745f34d9ee.squirrel@webmail-b.css.fujitsu.com> <9443f91bd4648e6214b32acff4512b97.squirrel@webmail-b.css.fujitsu.com> <20090728085810.f7ae678a.kamezawa.hiroyu@jp.fujitsu.com> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1132 Lines: 27 On Tue, 28 Jul 2009, KAMEZAWA Hiroyuki wrote: > > The nodemask for each task is updated to reflect the removal of a node and > > it calls mpol_rebind_mm() with the new nodemask. > > > yes, but _not_ updated at online. > Well, I disagreed that we needed to alter any pre-existing mempolicies for MEM_GOING_ONLINE or MEM_ONLINE since it may diverge from the original intent of the policy. MPOL_PREFERRED certain shouldn't change, MPOL_INTERLEAVE would be unbalanced, and MPOL_BIND could diverge from memory isolation or affinity requirements. I'd be interested to hear any real world use cases for MEM_ONLINE updating of mempolicies. > What I felt at reading cpuset/mempolicy again is that it's too complex ;) > The 1st question is why mems_allowed which can be 1024bytes when max_node=4096 > is copied per tasks.... The page allocator needs lockless access to mems_allowed. -- 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/