[Madwifi-users] [Fwd: hardware and kernel freezes accompanied with problematic BIOS]

[Peter P. <pet...@we...>]

Pushing this mail forward...

...does anybody have an idea?

Thanks in advance,

Peter Pinski

-------- Original-Nachricht --------
Betreff: hardware and kernel freezes accompanied with problematic BIOS
Datum: Tue, 30 Oct 2007 21:39:44 +0100
Von: Peter Pinski <pet...@we...>
An: mad...@li...

Hello,

I am running an x86_64 openSUSE 10.2 on a Dual Core Athlon X2. My
Desktop is a Dell Dimension E521 (nForce 430 chipset) and the wireless
PCI card I use is a D-Link DWL-G520 revision B.

I have the following problem: From time to time the card just freezes
without any error messages in dmesg or anything else. However, if I
remove the ath_pci module, reload it and set up the connection again,
the card works just fine - until it freezes ten or twenty minutes later.

This problem seems to be related to a bug in the power management (?) of
the BIOS: In the past my USB mouse or keyboard used to freeze from time
to time when I was working with Linux. If unplugging/replugging the
device into the USB port or reloading the USB core driver, they worked
just fine until the next freeze. There were also other people on the
Internet reporting the same problem, not only with Linux but also with
e.g. FreeBSD. If plugging the USB devices into a hub with an external
power supply, they worked flawlessly. Then, Dell released an updated
BIOS and after that the USB devices have not frozen any more if plugged
into the USB ports directly.

Now with the wireless card the symptoms are the same, so it seems they
have not solved the core of the problem. I have sent a mail to Dell's
support and they said they forwarded it to their technicians, but I have
not heard from them yet. So there may be a BIOS update tomorrow, maybe
there will never be one.

Thus I am applying an ugly hack: As there are no error messages when the
card freezes or anything helpful else, I have written a script that
pings the router every few seconds, and if there is no response,
wpa_supplicant and dhclient are terminated, the ath_pci module reloaded
and the connection set up again. And here the problems go:

1) The card freezes a few times an hour but from time to time the whole
of the operating system freezes. This happens no more often than once a
day, on some days it does not happen at all. I cannot discover any error
messages, not even anything unusual in /var/log/messages, the only thing
I can say is that the freezes always occur when dhclient is in the
process of fetching an IP address after reloading the kernel module. I
did not have any system freeze when loading the driver the first time
after starting the system yet. I do not know whether this is a bug in
the driver or not - can anyone think of a way to fix it?

2) Although it is done "automatically", it takes some time for the
kernel module to be reloaded and for the connection to be set up again.
I am sometimes annoyed if the connection is not up for some seconds
every ten or twenty minutes, especially if browsing the Internet. Is
there any way except an ugly Perl script to make the driver or the
kernel "wake" the card?

Thanks in advance,
Peter Pinski