From owner-freebsd-questions Sat Oct 24 19:09:37 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id TAA26219 for freebsd-questions-outgoing; Sat, 24 Oct 1998 19:09:37 -0700 (PDT) (envelope-from owner-freebsd-questions@FreeBSD.ORG) Received: from allegro.lemis.com (allegro.lemis.com [192.109.197.134]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id TAA26214 for ; Sat, 24 Oct 1998 19:09:34 -0700 (PDT) (envelope-from grog@freebie.lemis.com) Received: from freebie.lemis.com (freebie.lemis.com [192.109.197.137]) by allegro.lemis.com (8.9.1/8.9.0) with ESMTP id MAA04506; Sun, 25 Oct 1998 12:38:21 +1030 (CST) Received: (from grog@localhost) by freebie.lemis.com (8.9.1/8.9.0) id MAA16735; Sun, 25 Oct 1998 12:38:14 +1030 (CST) Message-ID: <19981025123814.C16609@freebie.lemis.com> Date: Sun, 25 Oct 1998 12:38:14 +1030 From: Greg Lehey To: Harlan Stenn , questions@FreeBSD.ORG Subject: Re: debugger("bt742a")? References: <4313.909249492@brown.pfcs.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.91.1i In-Reply-To: <4313.909249492@brown.pfcs.com>; from Harlan Stenn on Sat, Oct 24, 1998 at 01:18:12PM -0400 WWW-Home-Page: http://www.lemis.com/~grog Organization: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-41-739-7062 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Saturday, 24 October 1998 at 13:18:12 -0400, Harlan Stenn wrote: > I've been having a problem reading data off a tape drive. I run X, and the > tape would read for a while and eventually the machine would simply hang and > I could not change virtual consoles or do anything to find the problem. > > I tried reading the tape on another machine. Once it worked, two other > times I had the same problem. > > So I tried it again, but this time I did the restore from the vt0 instead > of in X. I noticed the kernel was dropping in to the debugger, with a > "tag" of bt742a. > > What's the real problem here, and what can be done to fix it? UTSL: $ find /usr/src/sys/ -name "*.c" | xargs grep bt742a /usr/src/sys/i386/scsi/bt.c: * Note: bt742a/747[s|d]/757/946/445s will return 'E' /usr/src/sys/i386/scsi/bt.c: u_char id[4]; /* i.e bt742a -> '7','4','2','A' */ /usr/src/sys/i386/scsi/bt.c: Debugger("bt742a"); Looking in that file, we find: /* * If the ccb's mbx is not free, then the board has gone Far East? */ if (bt_ccb_phys_kv(bt, ccb->mbx->ccb_addr) == ccb && ccb->mbx->cmd != BT_MBO_FREE) { printf("bt%d: not taking commands!\n", unit); Debugger("bt742a"); } In other words, you should have got an error message "bt0: not taking commands". Did you? I seem to remember having troubles reading tapes with a Buslogic controller years ago. In this case (BSDI machine), the SCSI subsystem just hung, reminding me every 30 seconds that it was hanging. It could be a Buslogic problem. Do you have machines with other controllers which you could try? You might also see if it works with the CAM drivers under 3.0. Greg -- See complete headers for address, home page and phone numbers finger grog@lemis.com for PGP public key To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message