On Fri, 16 Feb 1996 14:43:09 +0100 (GMT+0100) 
 Matthias Scheler <tron@colwyn.owl.de> wrote:

 > >Synopsis:       SCSI tape support broken

[ . . . ]

 > >Environment:
 > System: NetBSD colwyn 1.1A NetBSD 1.1A (COLWYN) #0: Sun Feb 11 23:35:43 GMT+0100 1996 tron@colwyn:/usr/src/sys/arch/i386/compile/COLWYN i386
 > 
 > >Description:
 > With a kernel compiled from 960215 sources I get an I/O error if I try to
 > access to my SCSI streamer with "tar". After reinstalling a 960210 kernel
 > it works fine again. My streamer is a Tandberg TDC 3660 connected to a
 > NCR 53c810.
 > 
 > >How-To-Repeat:
 > tron@colwyn:~>tar xvf /dev/nrst0
 > tar: can't open /dev/nrst0 : Input/output error

There's not really enough information here to even start debugging this.  
Firstly, does the kernel print anything on the console when the error 
occurs?  Maybe you could compile a kernel with SCSIDEBUG and get more 
information?  There are a number of places where st.c returns EIO to the 
user.  Maybe you could put some printfs in those places and tell us which 
one of those places is setting EIO?

Sorry, but "tar had an input/output error" is just to vague.  SCSI tape 
support is far from broken ... I use it almost every day.  It's not 
*perfect*, but... ;-)

--------------------------------------------------------------------------
Jason R. Thorpe                                       thorpej@nas.nasa.gov
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