Subject: Re: TOTAL CRASH after trying to use DMA and interrupts
To: Gordon Ross <>
From: Brett Glass <>
List: port-sun3
Date: 02/05/1996 13:02:50
> What kind of machine?  Note that the Sun3/50 has to use si_options=0
> until someone comes up with a work-around for the DMA hardware bug on the
> Sun3/50.

It's a Sun 3/50. The instructions didn't state clearly that I should not
change the mode of operation, so I tried. (This is something that SHOULD be
added to the readme!) I had to redo an Internet install, which took a whole

> What happened with the NetBSD boot tape?

The NetBSD boot tape could boot, but after the boot it could not operate
the drive properly. In other words, the RAM disk kernel could not read the
miniroot from the tape in order to copy it to the swap partition.
Even simple tape commands like mt -f /dev/nrst0 fsf 2 (i.e. positioning the
tape prior to loading the miniroot) did not work. mt -f /dev/nrst0 status
produces the message "7: unknown tape drive type."

Exactly the same thing happens when I issue the same commands from
the "full" NetBSD after it is installed.

SunOS never had any problem with the tape drive, but under NetBSD it is not