From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx113.postini.com [74.125.245.113]) by kanga.kvack.org (Postfix) with SMTP id 221876B0038 for ; Mon, 12 Aug 2013 10:50:45 -0400 (EDT) Message-ID: <1376318968.10300.334.camel@misato.fc.hp.com> Subject: Re: [PATCH v2] mm/hotplug: Verify hotplug memory range From: Toshi Kani Date: Mon, 12 Aug 2013 08:49:28 -0600 In-Reply-To: <20130811233722.GA27223@hacker.(null)> References: <1376162252-26074-1-git-send-email-toshi.kani@hp.com> <20130811233722.GA27223@hacker.(null)> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Wanpeng Li Cc: akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kosaki.motohiro@jp.fujitsu.com, kamezawa.hiroyu@jp.fujitsu.com, dave@sr71.net, isimatu.yasuaki@jp.fujitsu.com, tangchen@cn.fujitsu.com, vasilis.liaskovitis@profitbricks.com On Mon, 2013-08-12 at 07:37 +0800, Wanpeng Li wrote: > On Sat, Aug 10, 2013 at 01:17:32PM -0600, Toshi Kani wrote: > >add_memory() and remove_memory() can only handle a memory range aligned > >with section. There are problems when an unaligned range is added and > >then deleted as follows: > > > > - add_memory() with an unaligned range succeeds, but __add_pages() > > called from add_memory() adds a whole section of pages even though > > a given memory range is less than the section size. > > - remove_memory() to the added unaligned range hits BUG_ON() in > > __remove_pages(). > > > >This patch changes add_memory() and remove_memory() to check if a given > >memory range is aligned with section at the beginning. As the result, > >add_memory() fails with -EINVAL when a given range is unaligned, and > >does not add such memory range. This prevents remove_memory() to be > >called with an unaligned range as well. Note that remove_memory() has > >to use BUG_ON() since this function cannot fail. > > > >Signed-off-by: Toshi Kani > >Acked-by: KOSAKI Motohiro > >Reviewed-by: Tang Chen > > Reviewed-by: Wanpeng Li Thanks Wanpeng! -Toshi -- 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