From owner-freebsd-stable@FreeBSD.ORG Thu Dec 9 18:43:08 2004 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 3A7FB16A4CE; Thu, 9 Dec 2004 18:43:08 +0000 (GMT) Received: from avscan2.sentex.ca (avscan2.sentex.ca [199.212.134.19]) by mx1.FreeBSD.org (Postfix) with ESMTP id A98C343D1F; Thu, 9 Dec 2004 18:43:07 +0000 (GMT) (envelope-from mike@sentex.net) Received: from localhost (localhost.sentex.ca [127.0.0.1]) by avscan2.sentex.ca (8.12.11/8.12.11) with ESMTP id iB9Ih7KV086981; Thu, 9 Dec 2004 13:43:07 -0500 (EST) (envelope-from mike@sentex.net) Received: from avscan2.sentex.ca ([127.0.0.1]) by localhost (avscan2.sentex.ca [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 86308-07; Thu, 9 Dec 2004 13:43:07 -0500 (EST) Received: from lava.sentex.ca (pyroxene.sentex.ca [199.212.134.18]) by avscan2.sentex.ca (8.12.11/8.12.11) with ESMTP id iB9Ih6T2086973; Thu, 9 Dec 2004 13:43:06 -0500 (EST) (envelope-from mike@sentex.net) Received: from simian.sentex.net (simeon.sentex.ca [192.168.43.27]) by lava.sentex.ca (8.12.11/8.12.11) with ESMTP id iB9IgraH038998; Thu, 9 Dec 2004 13:42:59 -0500 (EST) (envelope-from mike@sentex.net) Message-Id: <6.2.0.14.0.20041209133753.0403b0c8@64.7.153.2> X-Mailer: QUALCOMM Windows Eudora Version 6.2.0.14 Date: Thu, 09 Dec 2004 13:43:32 -0500 To: Bruce Evans From: Mike Tancsa In-Reply-To: <20041208172619.Y1156@epsplex.bde.org> References: <200412062027.iB6KR1jE096684@www.freebsd.org> <20041207085811.P6480@epsplex.bde.org> <6.2.0.14.0.20041207100615.0335e328@64.7.153.2> <20041208172619.Y1156@epsplex.bde.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed X-Virus-Scanned: by amavisd-new X-Virus-Scanned: by amavisd-new at avscan2b cc: freebsd-gnats-submit@freebsd.org cc: freebsd-stable@freebsd.org Subject: Re: misc/74786: Smartlink Modem causes interrupt storm on RELENG_4 and RELENG_5 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 09 Dec 2004 18:43:08 -0000 [cc'ing to FreeBSD-Stable] Hi, I know that the proposed patches I submitted are not the best patches, but given that the next release of RELENG_4 is coming out, would it not be better to commit those to RELENG_4 as they allow the modem to work when it shares an interrupt with another device ? The sio and interrupt handling code in RELENG_5 is different enough that I doubt the patches you are proposing would make it back to RELENG_4. This at least lets the modem work and prevents the machine from locking up in an interrupt storm on RELENG_4 without breaking any functionality (as far as I know). ---Mike At 02:22 AM 08/12/2004, Bruce Evans wrote: >I think I understand this now. sio can indeed drive the interrupt (after >you open an sio device, but not immediately at the end of the attach >except in the serial console case). The main bugs are: >1. sio asks for exclusive access to the interrupt for no good reason > (some buses like isa might only support exclusive accesses, but sio > doesn't care). uhci gets access first in your configuration, so > allocation of the interrupt resource fails. >2. Error handling for the failure in (1) is null, so both devices are > "successfully" attached. >3. sio sets a flag to tell it to use polling if there is no interrupt > resource, but it doesn't set the flag if the interrupt resource > couldn't be allocated or if the interrupt couldn't be set up. >4. Upper layers provide negative help for debugging (3) using their > own version of (3). They print "irq N" in boot messages if an > interrupt resource justs exists. This doesn't mean that the device > is using it. >5. Device interrupts are still enabled in polling mode. This depends > on nothing else sucessfully setting up the (shared) interrupt.