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From: se@zpr.uni-koeln.de (Stefan Esser)
Date: Mon, 5 Feb 1996 16:30:10 +0100
In-Reply-To: Joakim Henriksson <murduth@ludd.luth.se>
       "SCSI reset broken." (Feb  5, 13:36)
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To: Joakim Henriksson <murduth@ludd.luth.se>
Subject: Re: SCSI reset broken.
Cc: bugs@freebsd.org
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On Feb 5, 13:36, Joakim Henriksson wrote:
} Subject: SCSI reset broken.
} >Submitter-Id:   current-user
} >Originator:     Joakim Henriksson
} >Organization:   Ludd
} >Confidential:   no
} >Synopsis:       SCSI reset hangs entire scsi bus
} >Severity:       serious
} >Priority:       medium
} >Category:       kernel
} >Release:        FreeBSD 2.1-STABLE i386
} >Class:          sw-bug
} >Environment:
} 
} NCR 810 SCSI
} SCSI disk
} SCSI cdrom
} SCSI streamer
} 
} but also on...
} AHA 2940
} SCSI disk
} SCSI disks (3 IBM AS/400 disks with 520b/sector :) )
} 
} >Description:
} 
} After using the streamer the bus gets a timeout from the device when it starts
} to rewind the tape and thus tries to reset the scsi bus, which is bad since it
} then loses contact with all devices. Causing my system to not work since swap
} and all lies on scsi disk :(
} 
} >How-To-Repat
} 
} echo "reset" | cdplay cd0
} or to use a device that is slow :)
} 
} >Fix:
} 
} None that i know of... Possibly longer timeout values on devicetimeout and
} scsi reset...

Could you please try the following patch 
and let me know, whether it helps:

Index: /sys/pci/ncr.c
===================================================================
RCS file: /usr/cvs/src/sys/pci/ncr.c,v
retrieving revision 1.56
retrieving revision 1.61
diff -C2 -r1.56 -r1.61
*** ncr.c	1996/01/10 21:20:57	1.56
--- ncr.c	1996/01/23 21:47:12	1.61
***************
*** 4427,4431 ****
  	OUTB (nc_stest2, EXT    );	/*  Extended Sreq/Sack filtering     */
  	OUTB (nc_stest3, TE     );	/*  TolerANT enable		     */
! 	OUTB (nc_stime0, 0xfb	);	/*  HTH = 1.6sec  STO = 0.1 sec.     */
  
  	/*
--- 4424,4428 ----
  	OUTB (nc_stest2, EXT    );	/*  Extended Sreq/Sack filtering     */
  	OUTB (nc_stest3, TE     );	/*  TolerANT enable		     */
! 	OUTB (nc_stime0, 0x0b	);	/*  HTH = disabled, STO = 0.1 sec.   */
  
  	/*



(The line numbers may be a little off,
since this is a diff obtained from the
FreeBSD-current version.)

Regards, STefan

-- 
 Stefan Esser, Zentrum fuer Paralleles Rechnen		Tel:	+49 221 4706021
 Universitaet zu Koeln, Weyertal 80, 50931 Koeln	FAX:	+49 221 4705160
 ==============================================================================
 http://www.zpr.uni-koeln.de/~se			  <se@ZPR.Uni-Koeln.DE>