From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262298AbTFOP2F (ORCPT ); Sun, 15 Jun 2003 11:28:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262299AbTFOP2F (ORCPT ); Sun, 15 Jun 2003 11:28:05 -0400 Received: from ns.suse.de ([213.95.15.193]:45580 "EHLO Cantor.suse.de") by vger.kernel.org with ESMTP id S262298AbTFOP2D (ORCPT ); Sun, 15 Jun 2003 11:28:03 -0400 To: "David S. Miller" Cc: James.Bottomley@steeleye.com, linux-kernel@vger.kernel.org Subject: Re: New struct sock_common breaks parisc 64 bit compiles with a misalignment References: <1055687753.10803.28.camel@mulgrave.suse.lists.linux.kernel> <20030615.073503.112613460.davem@redhat.com.suse.lists.linux.kernel> <1055690231.10803.54.camel@mulgrave.suse.lists.linux.kernel> <20030615.082355.08334189.davem@redhat.com.suse.lists.linux.kernel> From: Andi Kleen Date: 15 Jun 2003 17:41:53 +0200 In-Reply-To: <20030615.082355.08334189.davem@redhat.com.suse.lists.linux.kernel> Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.2 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 "David S. Miller" writes: > From: James Bottomley > Date: 15 Jun 2003 10:17:10 -0500 > > It's not necessary and would, indeed, be detrimental to operation since > we'd generate alignment traps on almost every encapsulated protocol (at > several hundred instructions per trap). If we do this, our network > performance will tank. > > It doesn't happen for all the normal cases, but it does for > things like IP in appletalk and stuff like that. It can be remotely triggered in ordinary TCP. Just add an odd number of nops before a TCP timestamp to misalign it. In short any linux parisc64 box on the net is very likely remotely panicable. -Andi