Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758862AbZJMCeK (ORCPT ); Mon, 12 Oct 2009 22:34:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758760AbZJMCeK (ORCPT ); Mon, 12 Oct 2009 22:34:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:61799 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758781AbZJMCeJ (ORCPT ); Mon, 12 Oct 2009 22:34:09 -0400 Message-ID: <4AD3E6C4.805@redhat.com> Date: Mon, 12 Oct 2009 22:32:36 -0400 From: Rik van Riel Organization: Red Hat, Inc User-Agent: Thunderbird 2.0.0.17 (X11/20080915) MIME-Version: 1.0 To: Wu Fengguang CC: Christian Borntraeger , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Andrew Morton , Elladan , Nick Piggin , Andi Kleen , Christoph Lameter , Peter Zijlstra , KOSAKI Motohiro , Johannes Weiner , Minchan Kim Subject: Re: oomkiller over-ambitious after "vmscan: make mapped executable pages the first class citizen" (bisected) References: <200910122244.19666.borntraeger@de.ibm.com> <20091013022650.GB7345@localhost> In-Reply-To: <20091013022650.GB7345@localhost> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1577 Lines: 44 Wu Fengguang wrote: > vmscan: limit VM_EXEC protection to file pages > > It is possible to have !Anon but SwapBacked pages, and some apps could > create huge number of such pages with MAP_SHARED|MAP_ANONYMOUS. These > pages go into the ANON lru list, and hence shall not be protected: we > only care mapped executable files. Failing to do so may trigger OOM. Good catch! The MAP_SHARED|MAP_ANONYMOUS segments may be backed by anonymous tmpfs files, instead of by actual anonymous memory! If this patch solves Christian's problem, I believe it should get merged into Linus's tree ASAP. > Reported-by: Christian Borntraeger > Signed-off-by: Wu Fengguang Reviewed-by: Rik van Riel > mm/vmscan.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > --- linux.orig/mm/vmscan.c 2009-10-13 09:49:05.000000000 +0800 > +++ linux/mm/vmscan.c 2009-10-13 09:49:37.000000000 +0800 > @@ -1356,7 +1356,7 @@ static void shrink_active_list(unsigned > * IO, plus JVM can create lots of anon VM_EXEC pages, > * so we ignore them here. > */ > - if ((vm_flags & VM_EXEC) && !PageAnon(page)) { > + if ((vm_flags & VM_EXEC) && page_is_file_cache(page)) { > list_add(&page->lru, &l_active); > continue; > } -- All rights reversed. -- 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/