From owner-freebsd-current@FreeBSD.ORG Sun Jun 17 08:50:10 2007 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 755D016A469 for ; Sun, 17 Jun 2007 08:50:10 +0000 (UTC) (envelope-from jmg@hydrogen.funkthat.com) Received: from hydrogen.funkthat.com (gate.funkthat.com [69.17.45.168]) by mx1.freebsd.org (Postfix) with ESMTP id 30DDA13C45D for ; Sun, 17 Jun 2007 08:50:10 +0000 (UTC) (envelope-from jmg@hydrogen.funkthat.com) Received: from hydrogen.funkthat.com (okge2ftgk218w76t@localhost.funkthat.com [127.0.0.1]) by hydrogen.funkthat.com (8.13.6/8.13.3) with ESMTP id l5H8LTEF035556 for ; Sun, 17 Jun 2007 01:21:29 -0700 (PDT) (envelope-from jmg@hydrogen.funkthat.com) Received: (from jmg@localhost) by hydrogen.funkthat.com (8.13.6/8.13.3/Submit) id l5H8LTZw035555 for freebsd-current@freebsd.org; Sun, 17 Jun 2007 01:21:29 -0700 (PDT) (envelope-from jmg) Date: Sun, 17 Jun 2007 01:21:28 -0700 From: John-Mark Gurney To: freebsd-current@freebsd.org Message-ID: <20070617082128.GW4602@funkthat.com> Mail-Followup-To: freebsd-current@freebsd.org References: <20070617024935.GU4602@funkthat.com> <20070616.211257.1585999818.imp@bsdimp.com> <20070617053746.GV4602@funkthat.com> <20070616.235659.-1947354616.imp@bsdimp.com> <20070617071303.GG12027@obelix.dsto.defence.gov.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070617071303.GG12027@obelix.dsto.defence.gov.au> User-Agent: Mutt/1.4.2.1i X-Operating-System: FreeBSD 5.4-RELEASE-p6 i386 X-Files: The truth is out there X-URL: http://resnet.uoregon.edu/~gurney_j/ X-Resume: http://resnet.uoregon.edu/~gurney_j/resume.html Subject: Re: kernel panic with pccard insert on recent 7.0 CURRENT X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: John-Mark Gurney List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 17 Jun 2007 08:50:10 -0000 Wilkinson, Alex wrote this message on Sun, Jun 17, 2007 at 15:13 +0800: > 0n Sat, Jun 16, 2007 at 11:56:59PM -0600, M. Warner Losh wrote: > > >Yes. I'm pretty sure that's wrong. All ISA and PC Card devices use > >edge triggered interrupts. Also, it is inefficient for level > >triggered interrupts, since two interrupt sources on the same > >interrupt may trigger at about the same time... > > What is meant by "edge triggered interrupts" ? Old ISA (edge) interrupts are only noticed when going from low (sometimes lines are driven opposite, I'm not sure which way ISA interrupt lines are driven) to high... This means that if you ack the interrupt, but the device never lowers the interrupt line, you will never see another low->high edge, and hence, never another interrupt from that line... PCI interrupts are level, which means as long as the interrupt line is "high" an interrupt will be delivered... This has the disadvantage that if you can't shut up the device, you get a storm and will need to disable that interrupt line... -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."