From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262162AbVFHKhC (ORCPT ); Wed, 8 Jun 2005 06:37:02 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262159AbVFHKhC (ORCPT ); Wed, 8 Jun 2005 06:37:02 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:47514 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S262162AbVFHKfs (ORCPT ); Wed, 8 Jun 2005 06:35:48 -0400 Subject: Re: [PATCH] Move some more structures into "mostly_readonly" From: Arjan van de Ven To: =?ISO-8859-1?Q?J=F6rn?= Engel Cc: Brian Gerst , christoph , Christoph Hellwig , akpm@osdl.org, linux-kernel@vger.kernel.org In-Reply-To: <20050608102053.GC331@wohnheim.fh-wedel.de> References: <20050607194123.GA16637@infradead.org> <1118177949.5497.44.camel@laptopd505.fenrus.org> <42A61227.9090402@didntduck.org> <20050608100056.GA331@wohnheim.fh-wedel.de> <1118225246.5655.16.camel@laptopd505.fenrus.org> <20050608102053.GC331@wohnheim.fh-wedel.de> Content-Type: text/plain; charset=UTF-8 Date: Wed, 08 Jun 2005 12:35:33 +0200 Message-Id: <1118226933.5655.19.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 (2.0.4-4) Content-Transfer-Encoding: 8bit X-Spam-Score: 3.7 (+++) X-Spam-Report: SpamAssassin version 2.63 on pentafluge.infradead.org summary: Content analysis details: (3.7 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 1.1 RCVD_IN_DSBL RBL: Received via a relay in list.dsbl.org [] 2.5 RCVD_IN_DYNABLOCK RBL: Sent directly from dynamic IP address [80.57.133.107 listed in dnsbl.sorbs.net] 0.1 RCVD_IN_SORBS RBL: SORBS: sender is listed in SORBS [80.57.133.107 listed in dnsbl.sorbs.net] X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2005-06-08 at 12:20 +0200, Jörn Engel wrote: > On Wed, 8 June 2005 12:07:25 +0200, Arjan van de Ven wrote: > > On Wed, 2005-06-08 at 12:00 +0200, Jörn Engel wrote: > > > On Tue, 7 June 2005 17:31:19 -0400, Brian Gerst wrote: > > > > > > > > It doesn't really matter. .rodata isn't actually mapped read-only. > > > > Doing so would break up the large pages used to map the kernel. > > > > > > Can you confirm that for every architecture? Or just i386? > > > > does it matter? it's supposed to be read only, only sometimes that's not > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > enforced unfortunately. > > I agree. What I don't agree with is "It doesn't really matter" - not > after debugging the occasional memory corruptions. I agree, and it would be very useful to have a debug option in the kernel that say checksums rodata (and probably the kernel text which is also read only) periodically and raises an alarm if the checksum changes.