From owner-freebsd-current Wed May 3 1:40:33 2000 Delivered-To: freebsd-current@freebsd.org Received: from anchor-post-34.mail.demon.net (anchor-post-34.mail.demon.net [194.217.242.92]) by hub.freebsd.org (Postfix) with ESMTP id C242537B861 for ; Wed, 3 May 2000 01:40:26 -0700 (PDT) (envelope-from dfr@nlsystems.com) Received: from nlsys.demon.co.uk ([158.152.125.33] helo=herring.nlsystems.com) by anchor-post-34.mail.demon.net with esmtp (Exim 2.12 #1) id 12muhk-000JoT-0Y; Wed, 3 May 2000 09:40:24 +0100 Received: from salmon.nlsystems.com (salmon.nlsystems.com [10.0.0.3]) by herring.nlsystems.com (8.9.3/8.8.8) with ESMTP id JAA47393; Wed, 3 May 2000 09:42:16 +0100 (BST) (envelope-from dfr@nlsystems.com) Date: Wed, 3 May 2000 09:45:28 +0100 (BST) From: Doug Rabson To: Matthew Dillon Cc: Gary Jennejohn , freebsd-current@freebsd.org Subject: Re: NFS, rl0 and Alpha In-Reply-To: <200005022114.OAA57726@apollo.backplane.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Tue, 2 May 2000, Matthew Dillon wrote: > > :Is anyone else observing kernel panics in the NFS code with Alpha > :(pc164) and rl0 (the Alpha is running as a client only) ? > : > :NFS worked just fine when I had a de0 in the box. After installing an > :rl0 (I know they suck, but they're so cheap :) I _always_ get an > :unaligned access panic when I try to access an NFS mounted FS, in any > :way. > > This is almost certainly related to differences in how the > packet is aligned in memory between de0 and rl0. > > If you are getting panics, it is probably at the same > location every time. If you can get a kernel core dump > and backtrace I'll bet we can find and fix this problem > quickly. Bill put workarounds for the alpha's alignment restrictions into some of his drivers but it seems that he missed out rl. Basically the part of the packet which includes headers needs to have the start of the ip header aligned to a 4-byte boundary. Since the preceding ethernet header is not padded to 4 bytes, this often means copying the first part of the packet to another mbuf. -- Doug Rabson Mail: dfr@nlsystems.com Nonlinear Systems Ltd. Phone: +44 20 8442 9037 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message