Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756720AbXL3TZ2 (ORCPT ); Sun, 30 Dec 2007 14:25:28 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753324AbXL3TZU (ORCPT ); Sun, 30 Dec 2007 14:25:20 -0500 Received: from E23SMTP05.au.ibm.com ([202.81.18.174]:51687 "EHLO e23smtp05.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750946AbXL3TZT (ORCPT ); Sun, 30 Dec 2007 14:25:19 -0500 Date: Mon, 31 Dec 2007 00:54:06 +0530 From: Dhaval Giani To: Ingo Molnar Cc: Christoph Lameter , Andrew Morton , Linus Torvalds , htejun@gmail.com, gregkh@suse.de, Srivatsa Vaddagiri , Balbir Singh , maneesh@linux.vnet.ibm.com, lkml , stable@kernel.org, linux-mm@kvack.org Subject: Re: 2.6.22-stable causes oomkiller to be invoked Message-ID: <20071230192406.GA10454@linux.vnet.ibm.com> Reply-To: Dhaval Giani References: <20071215035200.GA22082@linux.vnet.ibm.com> <20071214220030.325f82b8.akpm@linux-foundation.org> <20071215104434.GA26325@linux.vnet.ibm.com> <20071217045904.GB31386@linux.vnet.ibm.com> <20071217120720.e078194b.akpm@linux-foundation.org> <20071221044508.GA11996@linux.vnet.ibm.com> <20071230140116.GC21106@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20071230140116.GC21106@elte.hu> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1699 Lines: 43 On Sun, Dec 30, 2007 at 03:01:16PM +0100, Ingo Molnar wrote: > > * Christoph Lameter wrote: > > > Index: linux-2.6/arch/x86/mm/pgtable_32.c > > =================================================================== > > --- linux-2.6.orig/arch/x86/mm/pgtable_32.c 2007-12-26 12:55:10.000000000 -0800 > > +++ linux-2.6/arch/x86/mm/pgtable_32.c 2007-12-26 12:55:54.000000000 -0800 > > @@ -366,6 +366,15 @@ void pgd_free(pgd_t *pgd) > > } > > /* in the non-PAE case, free_pgtables() clears user pgd entries */ > > quicklist_free(0, pgd_dtor, pgd); > > + > > + /* > > + * We must call check_pgd_cache() here because the pgd is freed after > > + * tlb flushing and the call to check_pgd_cache. In some cases the VM > > + * may not call tlb_flush_mmu during process termination (??). > > that's incorrect i think: during process termination exit_mmap() calls > tlb_finish_mmu() unconditionally which calls tlb_flush_mmu(). > > > + * If this is repeated then we may never call check_pgd_cache. > > + * The quicklist will grow and grow. So call check_pgd_cache here. > > + */ > > + check_pgt_cache(); > > } > > so we still dont seem to understand the failure mode well enough. This > also looks like a quite dangerous change so late in the v2.6.24 cycle. > Does it really fix the OOM? If yes, why exactly? > No it does not. I've sent out some more information if it helps, will send to you separately. -- regards, Dhaval -- 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/