From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kamezawa Hiroyuki Subject: Re: [PATCH] slub: correctly bootstrap boot caches Date: Fri, 22 Feb 2013 20:15:48 +0900 Message-ID: <51275364.3010908@jp.fujitsu.com> References: <1361529030-17462-1-git-send-email-glommer@parallels.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1361529030-17462-1-git-send-email-glommer@parallels.com> Sender: owner-linux-mm@kvack.org List-ID: Content-Type: text/plain; charset="us-ascii" 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 (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 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org