Subject: Re: assertion "cp" failed.
To: Tatoku Ogaito <>
From: Dave Huang <>
List: current-users
Date: 09/05/1996 13:41:54
On Thu, 5 Sep 1996, Tatoku Ogaito wrote:
> Dear current-users,
> I bought 2 NCR 53c810 SCSI controllers for my PC last week.
> After upgrade my system, I receive following messages
> from kernel few times per day, and I cannot access any
> partition on sd2 at all.
> /netbsd: assertion "cp" failed: file "../../../../dev/pci/ncr.c", line 5748
> /netbsd: sd2(ncr1:3:0): COMMAND FAILED (4 28) @0xf88e1a00.

I believe this is an old timing bug in the NCR driver that occurs more
often when you have a very fast drive, or a slow computer... I was able to
work around the problem by adding:

options		SCSI_NCR_MAX_TAGS=0

to my kernel configuration file.

Suggestion for the NetBSD 1.2 release: perhaps the default should be to
have the tags turned off? A note could be included in a README somewhere
telling NCR users that they can turn tags on for faster performance, but
it might make their system unstable.
Name: Dave Huang     |   Mammal, mammal / their names are called /
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