Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751472AbXAPUcq (ORCPT ); Tue, 16 Jan 2007 15:32:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751469AbXAPUcq (ORCPT ); Tue, 16 Jan 2007 15:32:46 -0500 Received: from moutng.kundenserver.de ([212.227.126.188]:60711 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751481AbXAPUcp (ORCPT ); Tue, 16 Jan 2007 15:32:45 -0500 From: Bodo Eggert <7eggert@gmx.de> Subject: Re: O_DIRECT question To: Helge Hafting , Michael Tokarev , Chris Mason , Linus Torvalds , dean gaudet , Viktor , Aubrey , Hua Zhong , Hugh Dickins , linux-kernel@vger.kernel.org, hch@infradead.org, kenneth.w.chen@intel.com, akpm@osdl.org Reply-To: 7eggert@gmx.de Date: Tue, 16 Jan 2007 21:26:55 +0100 References: <7BYkO-5OV-17@gated-at.bofh.it> <7BYul-6gz-5@gated-at.bofh.it> <7C74B-2A4-23@gated-at.bofh.it> <7CaYA-mT-19@gated-at.bofh.it> <7Cpuz-64X-1@gated-at.bofh.it> <7Cz0T-4PH-17@gated-at.bofh.it> <7CBcl-86B-9@gated-at.bofh.it> <7CBvH-52-9@gated-at.bofh.it> <7DyYK-6lE-3@gated-at.bofh.it> User-Agent: KNode/0.7.2 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7Bit Message-Id: X-be10.7eggert.dyndns.org-MailScanner-Information: See www.mailscanner.info for information X-be10.7eggert.dyndns.org-MailScanner: Found to be clean X-be10.7eggert.dyndns.org-MailScanner-From: 7eggert@gmx.de X-Provags-ID: kundenserver.de abuse@kundenserver.de login:9b3b2cc444a07783f194c895a09f1de9 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 928 Lines: 18 Helge Hafting wrote: > Michael Tokarev wrote: >> But seriously - what about just disallowing non-O_DIRECT opens together >> with O_DIRECT ones ? >> > Please do not create a new local DOS attack. > I open some important file, say /etc/resolv.conf > with O_DIRECT and just sit on the open handle. > Now nobody else can open that file because > it is "busy" with O_DIRECT ? Suspend O_DIRECT access while non-O_DIRECT-fds are open, fdatasync on close? -- "Unix policy is to not stop root from doing stupid things because that would also stop him from doing clever things." - Andi Kleen "It's such a fine line between stupid and clever" - Derek Smalls - 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/