From owner-freebsd-alpha Wed Oct 14 10:40:17 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id KAA27051 for freebsd-alpha-outgoing; Wed, 14 Oct 1998 10:40:17 -0700 (PDT) (envelope-from owner-freebsd-alpha@FreeBSD.ORG) Received: from duke.cs.duke.edu (duke.cs.duke.edu [152.3.140.1]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id KAA27044 for ; Wed, 14 Oct 1998 10:40:15 -0700 (PDT) (envelope-from gallatin@cs.duke.edu) Received: from grasshopper.cs.duke.edu (grasshopper.cs.duke.edu [152.3.145.30]) by duke.cs.duke.edu (8.8.5/8.8.5) with ESMTP id NAA16013; Wed, 14 Oct 1998 13:39:53 -0400 (EDT) Received: (from gallatin@localhost) by grasshopper.cs.duke.edu (8.9.1/8.9.1) id NAA20718; Wed, 14 Oct 1998 13:39:29 -0400 (EDT) (envelope-from gallatin@cs.duke.edu) From: Andrew Gallatin MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Date: Wed, 14 Oct 1998 13:39:29 -0400 (EDT) To: Jason Thorpe Cc: Chris Csanady , freebsd-alpha@FreeBSD.ORG Subject: Re: kernel traps on boot.. In-Reply-To: <199810141710.KAA08380@lestat.nas.nasa.gov> References: <199810141710.KAA08380@lestat.nas.nasa.gov> X-Mailer: VM 6.43 under 20.4 "Emerald" XEmacs Lucid Message-ID: <13860.57411.377077.88475@grasshopper.cs.duke.edu> Sender: owner-freebsd-alpha@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Jason Thorpe writes: > > to the console. All unaligned accesses in the kernel are bugs, hence the > panic. Changing the kernel to fixup unaligned access in the kernel is > just plain wrong. In general I agree -- we found a really stupid performance bug in our Myrinet messaging system after we upgraded to DU4.0d (which doesn't fixup unaligned access faults in kernel mode) & realized we were taking an unaligned access trap in a certain chunk of frequently called code. However, I think its a perfectly acceptable temporary local hack when the unaligned access trap's are somebody else's fault & are preventing you from making forward progress on your own project.. Drew ------------------------------------------------------------------------------ Andrew Gallatin, Sr Systems Programmer http://www.cs.duke.edu/~gallatin Duke University Email: gallatin@cs.duke.edu Department of Computer Science Phone: (919) 660-6590 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-alpha" in the body of the message