From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx173.postini.com [74.125.245.173]) by kanga.kvack.org (Postfix) with SMTP id DE4EF6B004A for ; Wed, 29 Feb 2012 10:24:33 -0500 (EST) Date: Wed, 29 Feb 2012 09:24:30 -0600 (CST) From: Christoph Lameter Subject: Re: [PATCH -next] slub: set PG_slab on all of slab pages In-Reply-To: <1330505674-31610-1-git-send-email-namhyung.kim@lge.com> Message-ID: References: <1330505674-31610-1-git-send-email-namhyung.kim@lge.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Namhyung Kim Cc: Pekka Enberg , Matt Mackall , Namhyung Kim , linux-mm@kvack.org, linux-kernel@vger.kernel.org On Wed, 29 Feb 2012, Namhyung Kim wrote: > Unlike SLAB, SLUB doesn't set PG_slab on tail pages, so if a user would > call free_pages() incorrectly on a object in a tail page, she will get > confused with the undefined result. Setting the flag would help her by > emitting a warning on bad_page() in such a case. NAK You cannot free a tail page of a compound higher order page independently. You must free the whole compound. -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org