From owner-freebsd-hackers Mon Nov 3 06:19:38 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id GAA04833 for hackers-outgoing; Mon, 3 Nov 1997 06:19:38 -0800 (PST) (envelope-from owner-freebsd-hackers) Received: from hda.hda.com (hda-bicnet.bicnet.net [208.220.66.37]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id GAA04825 for ; Mon, 3 Nov 1997 06:19:34 -0800 (PST) (envelope-from dufault@hda.hda.com) Received: (from dufault@localhost) by hda.hda.com (8.8.5/8.8.5) id VAA03701; Sun, 2 Nov 1997 21:12:11 -0500 (EST) From: Peter Dufault Message-Id: <199711030212.VAA03701@hda.hda.com> Subject: Re: Strategy Routines In-Reply-To: <199711020252.NAA00521@word.smith.net.au> from Mike Smith at "Nov 2, 97 01:22:22 pm" To: mike@smith.net.au (Mike Smith) Date: Sun, 2 Nov 1997 21:12:09 -0500 (EST) Cc: hackers@freebsd.org X-Mailer: ELM [version 2.4ME+ PL25 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > > This is a fault in the driver design. Drivers should not hog the > cpu, obviously. Try calling tsleep() out of the driver with a very > short timeout. "fault" is too strong for the era this driver was written - I was punting back to the user process for a feature I'm not using. The size of the transfer you want to permit will vary based on the application, speed of hardware, etc, and I figured most people using this would know what they were up to. But now that FBSD is in wide use on the internet it points out a possible DOS hole for those few systems actually using the LabPC. Plus the questions I get about the LabPC driver via e-mail indicate that some of our users now expect the OS to always do the right thing. Peter -- Peter Dufault (dufault@hda.com) Realtime development, Machine control, HD Associates, Inc. Safety critical systems, Agency approval