Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 10 Mar 2003 06:55:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 10 Mar 2003 06:55:15 -0500 Received: from bay-bridge.veritas.com ([143.127.3.10]:23967 "EHLO mtvmime02.veritas.com") by vger.kernel.org with ESMTP id ; Mon, 10 Mar 2003 06:55:14 -0500 Date: Mon, 10 Mar 2003 12:07:43 +0000 (GMT) From: Hugh Dickins X-X-Sender: hugh@localhost.localdomain To: Ed Tomlinson cc: Dave McCracken , Andrew Morton , linux-kernel Subject: Re: [PATCH] nonlinear oddities In-Reply-To: <20030309013747.D394BC0@oscar.casa.dyndns.org> Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1262 Lines: 28 On Sat, 8 Mar 2003, Ed Tomlinson wrote: > Dave McCracken wrote: > > --On Thursday, March 06 2003, Hugh Dickins wrote: > > > >> Now I think about it more, install_page's SetPageAnon is not good at all. > >> That (unlocked) page may already be mapped into other vmas as a shared > >> file page, non-zero mapcount, we can't suddenly switch it to Anon > >> (pte_chained) without doing the work to handle that case. > > > > Ouch. You're right. I'll go stare at it for awhile and see if any > > solutions jump out at me. I suppose at worst I could write a function to > > convert an object page to use pte_chains, but it'd be nice if that weren't > > necessary. > > Does this look like the above happening? I very much doubt it. You'd have to be running an application using Ingo's new (since 2.5.46) remap_file_pages system call to suffer from Dave's ouch e.g. something like an experimental version of a major database app. That said, I've given no thought to what that ouch might look like in practice. Hugh - 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/