Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263097AbTH0K4V (ORCPT ); Wed, 27 Aug 2003 06:56:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263276AbTH0K4V (ORCPT ); Wed, 27 Aug 2003 06:56:21 -0400 Received: from bay-bridge.veritas.com ([143.127.3.10]:41506 "EHLO mtvmime03.VERITAS.COM") by vger.kernel.org with ESMTP id S263097AbTH0K4U (ORCPT ); Wed, 27 Aug 2003 06:56:20 -0400 Date: Wed, 27 Aug 2003 11:57:54 +0100 (BST) From: Hugh Dickins X-X-Sender: hugh@localhost.localdomain To: Andrew Morton cc: rusty@rustcorp.com.au, , Subject: Re: [PATCH 2/2] Futex non-page-pinning fix In-Reply-To: <20030827033836.17310dbc.akpm@osdl.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: 900 Lines: 22 On Wed, 27 Aug 2003, Andrew Morton wrote: > Hugh Dickins wrote: > > > > But I disagree over move_to/from_swap_cache: nothing should > > be done there at all. Once you have mapping,index in struct > > futex_q, it's irrelevant what tmpfs might be doing to the > > page->mapping,page->index of the unmapped page. > > But move_to_swap_cache() alters a page's ->mapping and ->index when that > page is potentially mapped into user pagetables. It'd better not: BUG_ON(page_mapped(page)) at start of shmem_writepage, sole caller of move_to_swap_cache. Things fall apart if tmpfs pages get reassigned to swap while they're mapped. 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/