2.6.22: USB getting stuck on SuperMicro PDSME+ boards

[Nikola Ciprich <extmaillist@linuxbox.cz>]

Hi,
I'm having problem with USB getting stuck on bunch of machines with PDSME+ boards (I haven't observed
the problem on any other type of board. Controller identifies as
8086:27c8 (rev 01) - Intel Corporation 82801G (ICH7 Family) USB UHCI Controller

Symptoms:
- any process trying to access /proc/bus/usb/devices gets stuck in 'D' state
- khubd seems to be stuck in 'D' state
- USB devices don't work

I'm observing the problem even on machines without any USB devs attached.
Unfortunately I wasn't able to reproduce the problem on my testing machines I have
on my disposal here (yet, but I'm still trying), and it's not affecting all PDSME+ boards we have deployed.
The problem appeared after upgrading machines to 2.6.24 kernels, we haven't observed it on 2.6.21 we used before.
On affected machines, kernel doesn't emit any OOPS, or anything else which could help to track. It just stops working after some time.

Bad thing is that since I'm not able to reproduce the problem here and I cannot reboot/upgrade production machines too
often, I can't provide much more information or try bisection :(
So this is rather desperate attempt to ask if anyone had similar problem or has any tip on where should I look to track it.
Kernels we're using are vanillas with few small unrelated patches applied.
Any help would be greatly appreciated
with best regards
nik


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Nikola CIPRICH
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