lots of panics in uPort V/386?

[Karl Denninger]

In article <115 at hawkmoon.UUCP> det at hawkmoon.UUCP (Derek E. Terveer) writes:
>Well, well, well -- comp.unix.microport is now unmoderated and root@<somewhere>
>said to "post your heads off", so i thought that i would interject a question
>to the assembled heads...
>
>I have recently purchased an ACER 1100 80386, 71M drive (miniscribe), 2.6M of
>memory (intel ps/286 above board) and am running 3.0-L2.2.  The problem is that
>i seem to be having lots of (relatively) unexplainable panics and i was
>wondering if anyone else with the 386 version was also having numbers of these
>panics, like "kernel mode traps" (type e), "user mode traps" (type 2 and 8),
>and "iupdat - iaddress >2^24" panics.  Plus i keep getting a number of "NMI in
>system mode" messages.  

The key one is the NMI message.

This can only be generated one way -- if your memory board(s) generate a
parity fault.  

16-bit boards have major problems in many of the 80386 systems.  Seems as
though some manufacturers didn't bother to insure DMA compatibility in the
extended memory region on 16-bit boards..... you can guess the result.

If you *do* have memory problems, the system will be flakey no matter what
you do.  It's quite possible that the only possible cure will be to replace
the 16-bit memory with 32-bit.....

Also note that the PS/286 above-board is not certified for operation 
at > 8Mhz on the bus.  Since I don't know the speed that the ACER clocks at
on the bus (note: CPU speed is not relavent here, it's BUS speed) I can't
speculate if the PS/286 card is simply incompatible with your I/O bus, or if
your '386 is one of the ones with the DMA problems.

If you can, try running with all 32-bit memory (even if you don't have a lot
-- slow is better than crashing!)

----
Karl Denninger		       |  Data: +1 312 566-8912
Macro Computer Solutions, Inc. | Voice: +1 312 566-8910
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