Re: AMD FX CPU bug, not fixed by latest microcode?

From: Boszormenyi Zoltan
Date: Wed Jun 13 2012 - 03:30:47 EST


2012-06-11 13:05 keltezéssel, Johannes Stezenbach írta:
On Mon, Jun 11, 2012 at 11:49:05AM +0200, Borislav Petkov wrote:
On Mon, Jun 11, 2012 at 10:43:18AM +0200, Borislav Petkov wrote:
On Sun, Jun 10, 2012 at 09:24:13PM +0200, Boszormenyi Zoltan wrote:
I have an AMD FX-8120 boxed CPU in an ASUS M5A99X-EVO mainboard
with 32GB DDR3/1600 memory, running Fedora 17, upgraded from 16.
memtest86+ show no problems.
Ohe other thing: if there's an option in the BIOS to disable the IOMMU,
can you do that and try reproducing the issue with IOMMU disabled?
Maybe not related, but I had bad memory in my Intel Core-i5
based system some months ago which resulted in rare crashes,
usually manifested itself as g++ ICEs when compiling a
mid-sized C++ project -- compiling a kernel with make -p4 showed
no problem. Also memtest86+ didn't show the issue,
so I tried memtest86-4.0a which claims to find more errors
due to SMP support. An overnight run left me with a screen
full of garbage and a crashed memtest86-4.0. I replaced
the RAM anyway and the box was stable since then.

memtest86-4.0a is at
http://memtest86.com/

The page claims:
With a single CPU it is not possible to drive multi-channel memory
controllers at full speed making it impossible to detect some types of errors

Maybe someone knowledgable could comment if this is true.

This one locked up on my machine but memtest86+ 4.20 detected
12 different addresses with faulty bits in the lower 16GB. Applying
for warranty.

With only two modules, "make -j8" succeeded a lot of times.

Thanks for everyone who tried to help.

Best regards,
Zoltán Böszörményi

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/