DMA errors

[Ted Mittelstaedt]

>-----Original Message-----
>From: owner-freebsd-questions at freebsd.org
>[mailto:owner-freebsd-questions at freebsd.org]On Behalf Of Mike Jeays
>Sent: Saturday, November 05, 2005 4:18 PM
>To: Ted Mittelstaedt
>Cc: freebsd-questions at freebsd.org
>Subject: RE: DMA errors
>
>
>On Mon, 2005-10-31 at 08:00, Mike Jeays wrote:
>> On Mon, 2005-10-31 at 02:11, Ted Mittelstaedt wrote:
>> > >-----Original Message-----
>> > >From: Mike Jeays [mailto:Mike.Jeays at rogers.com]
>> > >Sent: Saturday, October 29, 2005 8:04 PM
>> > >To: Ted Mittelstaedt
>> > >Cc: freebsd-questions at freebsd.org
>> > >Subject: RE: DMA errors
>> > >
>> > >
>> > >On Sat, 2005-10-29 at 19:48, Ted Mittelstaedt wrote:
>> > >> Try a different disk drive.
>> > >>
>> > >> What motherboard is in use here?
>> > >>
>> > >> Ted
>> > >>
>> > >> >-----Original Message-----
>> > >> >From: owner-freebsd-questions at freebsd.org
>> > >> >[mailto:owner-freebsd-questions at freebsd.org]On Behalf
>Of Mike Jeays
>> > >> >Sent: Saturday, October 29, 2005 4:28 PM
>> > >> >To: freebsd-questions at freebsd.org
>> > >> >Subject: DMA errors
>> > >> >
>> > >> >
>> > >> >I have a 40GB Maxtor D740X-6L disk, and have been unable to
>> > >install 5.4
>> > >> >or 6.0 on it.  I get errors:
>> > >> >
>> > >> >ad0: FAILURE WRITE_DMA STATUS=51 <READY,DSC,ERROR>
>error=84 (IRC,
>> > >> >ABORTED) LBA=..
>> > >> >
>> > >> >as soon as I try to commmit the changes in sysinstall.
>> > >> >
>> > >> >I have checked that the IDE cable is the 80-wire type,
>and cleaned up
>> > >> >the connections and so on.
>> > >> >
>> > >> >I tried installing Ubuntu on this disk, and everything went
>> > >perfectly.
>> > >> >(Those guys have done a really great job, by the way).
>> > >> >
>> > >> >Is there some configuration trick I have missed?
>> > >> >
>> > >> >_______________________________________________
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>> > >> >http://lists.freebsd.org/mailman/listinfo/freebsd-questions
>> > >> >To unsubscribe, send any mail to
>> > >> >"freebsd-questions-unsubscribe at freebsd.org"
>> > >> >
>> > >> >--
>> > >> >No virus found in this incoming message.
>> > >> >Checked by AVG Free Edition.
>> > >> >Version: 7.1.362 / Virus Database: 267.12.6/151 - Release Date:
>> > >> >10/28/2005
>> > >> >
>> > >
>> > >It works on at least one other disk, a Western Digital 80GB.  The
>> > >motherboard is as Asus P4S533.
>> > >
>> >
>> > Well I hate to be flippant, but there you have it, problem solved.
>> >
>> > I have been doing PC work professionally for over 10 years and
>> > unprofessionally for at least 10-15 years before that, and ever
>> > since the IDE interface was invented I've had to deal with
>> > incompatibilties between the controller and the hard disk.  Back
>> > in the days that the IDE controller chip was on a paddle card I
>> > used to have a box of them and when running into a problem like
>> > your doing, I would swap the cards until I got a good combo.  This
>> > was all ISA stuff of course.  Once the PCI came out and they
>> > started putting the controller on motherboard, they only way around
>> > these problems is to play musical chairs with the disk drives.
>> >
>> > And all this was long before FreeBSD, let alone Linux, was even
>> > a gleam in someone's eye.
>> >
>> > Your 40GB Maxtor has some moronic timing incompatibility with the
>> > IDE chipset that the FreeBSD driver in 5.4/6.0 happens to tickle,
>> > there's nothing you can do about it.  Use your 80GB disk for the
>> > FreeBSD system or go find some other brand of motherboard for your
>> > 40GB disk, and things will work fine.
>> >
>> > Ted
>> >
>> > _______________________________________________
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>> > http://lists.freebsd.org/mailman/listinfo/freebsd-questions
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>"freebsd-questions-unsubscribe at freebsd.org"
>>
>> Thanks for the advice, and that is probably what I will do.
>>
>> However, before I bought the 80GB disk, I used to run 4.6 on
>the Maxtor
>> 40GB, with no problems.  Furthernore, this disk and MB will still run
>> Ubuntu and Fedora, so it seems that later FreeBSD releases are more
>> sensitive, or drive the hardware a bit harder.
>>
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>
>Thanks for the help - you seem to be correct, Ted.  I bought a second
>Western Digital 80GB disk, and 5.4 installs on this with no problem.
>
>The case for the 40 GB Maxtor seems a little odd - it works fine with
>Ubuntu, the Redmond product, and Fedora Core 3. I even switched it to
>PIO-only mode, and then 5.4 can be installed - but, as expected, it is
>very slow - 25 seconds to load KPresenter, for example.  Not too useful.
>
>It also worked with an earlier FreeBSD, version 4.7 and before.  So does
>FreeBSD drives disks a bit harder than other OSes, and is it still "in
>spec"?
>

I think the issue is that you have to view the computer as a true
merger of hardware and software, not simply a hardware platform that
software happens to be running on.

With the FreeBSD OS (and in any OS) there's many abstractive layers
to try to decouple as much of the code as possible from the hardware.
For example you do not want your network card shutting down just because
a particular usermode app runs, that is why the OS prohibits those apps
from doing so.

But, despite all this what it all boils down to is the CPU of the
motherboard
is just executing a long sequence of 1's and 0s.  In any given moment
that
code executing in the CPU could be a usermode program, a kernel device
driver, or whatever.  If the hardware isn't acting as expected, you will
get all manner of unexplained, random issues.

You could probably install 5.4 fine on that 40GB disk if you put it
in a different PC.

Ted