Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754153Ab0DLVEa (ORCPT ); Mon, 12 Apr 2010 17:04:30 -0400 Received: from mx1.redhat.com ([209.132.183.28]:19039 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752776Ab0DLVE3 (ORCPT ); Mon, 12 Apr 2010 17:04:29 -0400 Message-ID: <4BC38A94.2050003@redhat.com> Date: Mon, 12 Apr 2010 17:03:16 -0400 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.7) Gecko/20100120 Fedora/3.0.1-1.fc12 Lightning/1.0b2pre Thunderbird/3.0.1 MIME-Version: 1.0 To: Linus Torvalds CC: Borislav Petkov , Johannes Weiner , KOSAKI Motohiro , Andrew Morton , Minchan Kim , Linux Kernel Mailing List , Lee Schermerhorn , Nick Piggin , Andrea Arcangeli , Hugh Dickins , sgunderson@bigfoot.com Subject: Re: [PATCH 4/4] anonvma: when setting up page->mapping, we need to pick the _oldest_ anonvma References: <20100411130801.GA7189@a1.tnic> <20100411185508.GA4450@liondog.tnic> <20100412072056.GA2432@liondog.tnic> <4BC36916.3080005@redhat.com> <20100412190002.GA8595@a1.tnic> In-Reply-To: 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: 1299 Lines: 29 On 04/12/2010 04:23 PM, Linus Torvalds wrote: > > From: Linus Torvalds > Date: Mon, 12 Apr 2010 12:44:29 -0700 > Subject: [PATCH 4/4] anonvma: when setting up page->mapping, we need to pick the _oldest_ anonvma > > Otherwise we might be mapping in a page in a new mapping, but that page > (through the swapcache) would later be mapped into an old mapping too. > The page->mapping must be the case that works for everybody, not just > the mapping that happened to page it in first. > > This can be improved in certain cases: if we know the page is private to > just this particular mapping (for example, it's a new page, or it is the > only swapcache entry), we could pick the top (most specific) anon_vma. > > But that's a future optimization. Make it _work_ reliably first. Agreed. I'll send an incremental for that later, you can judge whether or not it's something you'll want to merge before or after 2.6.34 > Signed-off-by: Linus Torvalds Reviewed-by: Rik van Riel -- 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/