Re: [tboot-devel] tboot broke my laptop! (twice!)

[Tondapu, K. <kar...@hp...>]

Hi Hal,
The last time I checked tboot on 6930p was with Changeset:d9eaaaa7279b and BIOS:F.10 and I haven't seen any issues (no hang or restart). The txt-stat log looked fine too. Can you please tell me which bios version you are using? 

Will have to check if any recent changes to tboot are breaking on the unit.

Karthik

-----Original Message-----
From: Hal Finney [mailto:hal...@gm...] 
Sent: Sunday, August 16, 2009 11:14 AM
To: tbo...@li...
Cc: Tondapu, Karthik
Subject: tboot broke my laptop! (twice!)

I was traveling recently, and I wanted to do some experiments with TXT
on the road, so I bought an HP laptop that supports the technology. It
is an HP EliteBook 6930p. I got it set up with Linux and tboot,
enabled TPM, VT and TXT, and tried booting tboot and a Linux kernel.

Something went wrong. My laptop hung and I restarted it. But it didn't
start properly. The power light and other lights came on, but the
display did not light up. The fan started and disk began spinning, but
after about a second, the whole thing powered down. The fan and disk
stopped, and all of the lights went out. Then, after a few seconds, it
turned itself back on. But once again, after starting the fan and
disk, and before lighting the display, the laptop shut off. This cycle
would repeat indefinitely, the laptop turning itself on and off. I
have to make it stop by pressing and holding the power button.

In short, my laptop was completely broken and useless.

Fortunately, being new it was covered by HP's warranty. They talked me
through the usual minor fixits on the phone, removing the disk and
such, and nothing helped. They finally told me to take it to an
authorized repair shop. The nearest one is 80 miles away so it was not
super convenient, but I did it. Unfortunately it meant that I was not
able to take the laptop on my trip and was not able to do my
experiments.

I got back this week and picked up my laptop from the repair shop.
They had replaced the motherboard and it worked fine. So I tried
again. I enabled the new TPM, got VT and TXT enabled, and tried
launching tboot.

It broke again.

Once again my laptop is useless. It repeatedly turns itself on and
off, and does not even light up the display. It does not get far
enough into BIOS to boot from a CD or any other medium.

I am a little worried about once again demanding that HP fix this
machine under the terms of my warranty. I did not go into any detail
about what I was doing when it broke the first time. In fact I thought
it was probably just a defective machine; I did not necessarily
connect it that much with tboot since I was just getting started with
it and had only used it for an hour or so. But with the same thing
happening twice now, it is clear that I am breaking it. And I am not
running Windows, I am using experimental software, etc. Of course the
machine is claimed to support TXT, so obviously it should not break
from running tboot. But this is such a little-known and new technology
that I'm sure only a few people at HP are familiar with it. I am not
sure how to proceed with regard to the warranty.

I wonder if anyone at HP reading this might be able to comment? It
will not be good if HP laptops are turned into bricks by running
tboot.

Hal Finney