Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751145AbVKNPHx (ORCPT ); Mon, 14 Nov 2005 10:07:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751147AbVKNPHx (ORCPT ); Mon, 14 Nov 2005 10:07:53 -0500 Received: from taurus.voltaire.com ([193.47.165.240]:39461 "EHLO taurus.voltaire.com") by vger.kernel.org with ESMTP id S1751145AbVKNPHw (ORCPT ); Mon, 14 Nov 2005 10:07:52 -0500 Date: Mon, 14 Nov 2005 17:07:03 +0200 From: Gleb Natapov To: "Michael S. Tsirkin" Cc: Hugh Dickins , Benjamin Herrenschmidt , Petr Vandrovec , Nick Piggin , Badari Pulavarty , Linux Kernel Mailing List Subject: Re: Nick's core remove PageReserved broke vmware... Message-ID: <20051114150703.GH5492@minantech.com> References: <20051114145708.GU20871@mellanox.co.il> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20051114145708.GU20871@mellanox.co.il> X-OriginalArrivalTime: 14 Nov 2005 15:07:46.0637 (UTC) FILETIME=[2BBA7FD0:01C5E92D] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1243 Lines: 37 On Mon, Nov 14, 2005 at 04:57:08PM +0200, Michael S. Tsirkin wrote: > Quoting r. Hugh Dickins : > > Subject: Re: Nick's core remove PageReserved broke vmware... > > > > On Mon, 14 Nov 2005, Michael S. Tsirkin wrote: > > > Quoting Gleb Natapov : > > > > On Mon, Nov 14, 2005 at 02:25:35PM +0200, Michael S. Tsirkin wrote: > > > > > > > > > > There's one thing that I have thought about: what happens > > > > > if I set DONTFORK on a page which already has COW set > > > > > (e.g. after fork)? > > > > > > > > > > It seems that the right thing would be to force a page copy - > > > > > otherwise the page can get copied on write. > > > > > Should we worry about this? > > > > About what? > > For pages which hardware will only read, not write, > hardware driver does get_user_pages with write cleared. > It looks like openib always pass 1 as write. I think this is exactly for this reason. > This means that COW may remain set. > > -- > MST -- Gleb. - 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/