From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751156AbVIURVl (ORCPT ); Wed, 21 Sep 2005 13:21:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751166AbVIURVl (ORCPT ); Wed, 21 Sep 2005 13:21:41 -0400 Received: from smtp002.mail.ukl.yahoo.com ([217.12.11.33]:35190 "HELO smtp002.mail.ukl.yahoo.com") by vger.kernel.org with SMTP id S1751156AbVIURVk (ORCPT ); Wed, 21 Sep 2005 13:21:40 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.it; h=Received:From:To:Subject:Date:User-Agent:Cc:References:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-Disposition:Message-Id; b=UEayBSUypfJDE1OzRii4VjQpFBEah5nA0QEugWPMC5F7Iq5wqXS7QMqGV9Lm/51KordE7B+9BYxn541iJ7Thc7hQXQn1NMFYt1KTxS3te/nQpJuN4Ii71gp1HRV5O5w8cfsMwFbsPG5PKbhtbE9emukKyvcNokPqZh+QVaSA2GA= ; From: Blaisorblade To: Hugh Dickins Subject: Re: Remap_file_pages, RSS limits, security implications (was: Re: [uml-devel] Re: [RFC] [patch 0/18] remap_file_pages protection support (for UML), try 3) Date: Wed, 21 Sep 2005 19:02:25 +0200 User-Agent: KMail/1.8.2 Cc: Rik van Riel , Andrew Morton , LKML , Ingo Molnar References: <200508262023.29170.blaisorblade@yahoo.it> <200509211816.37512.blaisorblade@yahoo.it> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200509211902.25989.blaisorblade@yahoo.it> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 21 September 2005 18:50, Hugh Dickins wrote: > On Wed, 21 Sep 2005, Blaisorblade wrote: > > Other pages in the VMA may be unmapped, yes, but not freed. In fact, > > they're kept in by the pagecache reference; try_to_unmap() (or better its > > caller, shrink_list) will only actually free the page it asked for. > Not freed in that pass, yes; but brought closer to being freed soon. Will a page with mapcount == 0 be put in the inactive list explicitly? At next scan PageActive will be clear, sure, and it won't be reactivated while it's unmapped. But references will only cause more hardware faults. > > The only real "problem" is that we do ptep_clear_flush_young without > > activating the page. And yes, *this* may penalize who holds a nonlinear > > VMA. But this is probably fair, given that we're going to have trouble in > > freeing those pages. > Good point, I don't remember ever considering that. > But agree it should work out fairly. > > > mm/trash.c? I got quite excited, > > What would that have meant? > Trash is rubbish or garbage. Or if I trash my hotel room (not me!), > I'd rip the washbasin off the wall, smash the mirror, throw the > chair through the window, ... hmm, better stop this public fantasy. Nice... hope this can get to LWN "quotes of the week" page. -- Inform me of my mistakes, so I can keep imitating Homer Simpson's "Doh!". Paolo Giarrusso, aka Blaisorblade (Skype ID "PaoloGiarrusso", ICQ 215621894) http://www.user-mode-linux.org/~blaisorblade ___________________________________ Yahoo! Mail: gratis 1GB per i messaggi e allegati da 10MB http://mail.yahoo.it