Subject: Re: SCSI Timeout panic: how to fix?
To: None <macbsd-general@NetBSD.ORG>
From: David Condon <>
List: macbsd-general
Date: 02/23/1995 12:49:17
>I'm getting an odd crash. I get this:
>scsi timeout--WAIT_FOR_REQ---scsi.c, line 711.
>and then the system hangs (no panic).
>My kernel is compiled straight from the NetBSD-1.0 sources, except for
>the changes to the scsi_done, sdstrategy, and sdstart routines suggested by
> on this list to fix the biodone already errors.

I have never experienced that error, but I'm not surprised that somebody
would have a problem, because the suggestion I offered does not in any way
shape or form constitute a "fix." It probably just happens to work on  my
system due to chaotic conditions relating to the moons of Neptune.

>I experienced the SCSI timeout errors even on the netbsd.patched kernel
>on cray-ymp.

Did it hang with netbsd.patched, or did you just get the error message? In
other words was the behavior the same. If so it's possibly unrelated to
the biodone already thing.

Did you apply the patches from the README.late file on cray? This was dated
about 3 days after the release of 1.0. If I remember, if you started out
with the ksrc-10 archive package, you need to apply those patches and then
your build will be equivalent to netbsd.patched. Somebody correct me if I'm

>Looking over the SCSI .c files and David's changes to them, I think
>I see the reason... the WAIT_FOR_REQ macro gotos scsi_timeout_error,
>which returns to the caller, and (I surmise--I haven't had time yet
>to go over this with adb) the caller would have called biodone(),
>but doesn't because David's if statement evaluates false.
>I don't know much about either SCSI or the NetBSD kernel, and as it's
>midterm exam season, I don't have the time to try and understand it...
>does anyone know how to get rid of these? Should I try compiling with
>-current? I gave -current a cursory glance, but couldn't get even
>as far as the config step. Probably I was doing something really stupid;
>I'll try again tomorrow with -current.
>Thanks a lot!
>        -Ben

      "The Net interprets censorship as damage and routes around it."
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