Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751139AbVLGPmO (ORCPT ); Wed, 7 Dec 2005 10:42:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751147AbVLGPmO (ORCPT ); Wed, 7 Dec 2005 10:42:14 -0500 Received: from pat.uio.no ([129.240.130.16]:22242 "EHLO pat.uio.no") by vger.kernel.org with ESMTP id S1751139AbVLGPmO (ORCPT ); Wed, 7 Dec 2005 10:42:14 -0500 Subject: Re: another nfs puzzle From: Trond Myklebust To: Peter Staubach Cc: Kenny Simpson , linux-kernel@vger.kernel.org In-Reply-To: <4397011E.9010703@redhat.com> References: <20051206220448.82860.qmail@web34109.mail.mud.yahoo.com> <4396EB2F.3060404@redhat.com> <1133964667.27373.13.camel@lade.trondhjem.org> <4396EF50.30201@redhat.com> <1133966063.27373.29.camel@lade.trondhjem.org> <4397011E.9010703@redhat.com> Content-Type: text/plain Date: Wed, 07 Dec 2005 10:41:57 -0500 Message-Id: <1133970117.27373.53.camel@lade.trondhjem.org> Mime-Version: 1.0 X-Mailer: Evolution 2.4.1 Content-Transfer-Encoding: 7bit X-UiO-Spam-info: not spam, SpamAssassin (score=-3.715, required 12, autolearn=disabled, AWL 1.10, FORGED_RCVD_HELO 0.05, RCVD_IN_SORBS_DUL 0.14, UIO_MAIL_IS_INTERNAL -5.00) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 856 Lines: 20 On Wed, 2005-12-07 at 10:34 -0500, Peter Staubach wrote: > This seems like a dangerous enough area that denying mmap on a file which > has been opened with O_DIRECT by any process and denying open(O_DIRECT) > on a file which has been mmap'd would be a good thing. These things are > easy enough to keep track of, so it shouldn't be too hard to implement. That would be a recipe for DOSes as it would allow one process to block another just by opening a file. I'd really not like to see my database crash just because some obscure monitoring program happens to use mmap() to browse the file. Cheers, Trond - 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/