From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756902Ab3BVLQS (ORCPT ); Fri, 22 Feb 2013 06:16:18 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:50272 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755756Ab3BVLQM (ORCPT ); Fri, 22 Feb 2013 06:16:12 -0500 X-SecurityPolicyCheck: OK by SHieldMailChecker v1.8.4 Message-ID: <51275364.3010908@jp.fujitsu.com> Date: Fri, 22 Feb 2013 20:15:48 +0900 From: Kamezawa Hiroyuki User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:17.0) Gecko/20130107 Thunderbird/17.0.2 MIME-Version: 1.0 To: Glauber Costa CC: linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Christoph Lameter , Andrew Morton , Tejun Heo , Pekka Enberg Subject: Re: [PATCH] slub: correctly bootstrap boot caches References: <1361529030-17462-1-git-send-email-glommer@parallels.com> In-Reply-To: <1361529030-17462-1-git-send-email-glommer@parallels.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (2013/02/22 19:30), Glauber Costa wrote: > After we create a boot cache, we may allocate from it until it is bootstraped. > This will move the page from the partial list to the cpu slab list. If this > happens, the loop: > > list_for_each_entry(p, &n->partial, lru) > > that we use to scan for all partial pages will yield nothing, and the pages > will keep pointing to the boot cpu cache, which is of course, invalid. To do > that, we should flush the cache to make sure that the cpu slab is back to the > partial list. > > Although not verified in practice, I also point out that it is not safe to scan > the full list only when debugging is on in this case. As unlikely as it is, it > is theoretically possible for the pages to be full. If they are, they will > become unreachable. Aside from scanning the full list, we also need to make > sure that the pages indeed sit in there: the easiest way to do it is to make > sure the boot caches have the SLAB_STORE_USER debug flag set. > > Signed-off-by: Glauber Costa > Reported-by: Steffen Michalke > Cc: Christoph Lameter > Cc: Andrew Morton > Cc: Tejun Heo > Cc: Pekka Enberg > Cc: Kamezawa Hiroyuki > You're quick :) the issue is fixed in my environ. Tested-by: KAMEZAWA Hiroyuki