Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753024Ab1BVKDG (ORCPT ); Tue, 22 Feb 2011 05:03:06 -0500 Received: from gir.skynet.ie ([193.1.99.77]:34105 "EHLO gir.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751335Ab1BVKDE (ORCPT ); Tue, 22 Feb 2011 05:03:04 -0500 Date: Tue, 22 Feb 2011 10:02:36 +0000 From: Mel Gorman To: Petr Holasek Cc: linux-kernel@vger.kernel.org, Andi Kleen , Naoya Horiguchi , Andrew Morton , Wu Fengguang , linux-mm@kvack.org Subject: Re: [PATCH] hugetlbfs: correct handling of negative input to /proc/sys/vm/nr_hugepages Message-ID: <20110222100235.GA15652@csn.ul.ie> References: <1298303270-3184-1-git-send-email-pholasek@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <1298303270-3184-1-git-send-email-pholasek@redhat.com> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1440 Lines: 47 On Mon, Feb 21, 2011 at 04:47:49PM +0100, Petr Holasek wrote: > When user insert negative value into /proc/sys/vm/nr_hugepages it will result > in the setting a random number of HugePages in system (can be easily showed > at /proc/meminfo output). I bet you a shiny penny that the value of HugePages becomes the maximum number that could be allocated by the system at the time rather than a random value. > This patch fixes the wrong behavior so that the > negative input will result in nr_hugepages value unchanged. > As pointed out elsewhere, nr_overcommit_hugepages also needs fixing but the fix is essentially the same. > Signed-off-by: Petr Holasek > --- > mm/hugetlb.c | 3 +-- > 1 files changed, 1 insertions(+), 2 deletions(-) > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index bb0b7c1..f99d7a8 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -1872,8 +1872,7 @@ static int hugetlb_sysctl_handler_common(bool obey_mempolicy, > unsigned long tmp; > int ret; > > - if (!write) > - tmp = h->max_huge_pages; > + tmp = h->max_huge_pages; > > if (write && h->order >= MAX_ORDER) > return -EINVAL; > -- > 1.7.1 > -- Mel Gorman SUSE Labs -- 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/