Re: USB OOPS 2.6.25-rc2-git1

[David Brownell <david-b@pacbell.net>]

On Wednesday 20 February 2008, Andre Tomt wrote:
> ehci_hcd 0000:00:1d.7: IAA watchdog, lost IAA: status 8029 cmd 10021
> ehci_hcd 0000:00:1d.7: IAA watchdog, lost IAA: status 8029 cmd 10021
> ehci_hcd 0000:00:1d.7: IAA watchdog, lost IAA: status 8029 cmd 10021
> ehci_hcd 0000:00:1d.7: IAA watchdog, lost IAA: status 8029 cmd 10021
> ehci_hcd 0000:00:1d.7: IAA watchdog, lost IAA: status 8029 cmd 10021
> ehci_hcd 0000:00:1d.7: IAA watchdog, lost IAA: status 8028 cmd 10021
> ehci_hcd 0000:00:1d.7: IAA watchdog, lost IAA: status 8028 cmd 10021
> ehci_hcd 0000:00:1d.7: IAA watchdog, lost IAA: status 8028 cmd 10021
> ehci_hcd 0000:00:1d.7: IAA watchdog, lost IAA: status 8029 cmd 10021

... etc.

OK, the relevant bits are:

   status  0001 == some transaction completed normally (ignored here)
   status  0020 == IAA set, which should have triggered an IRQ
   command 0040 == IAAD clear, meaning IAA should have triggered

Meaning the hardware is misbehaving in a "traditional" way, one
that the watchdog is supposed to catch:  IAA set, but no IRQ.

If you see any "IAA" messages *other* than those, please report
them ASAP.  They'll indicate "nontraditional" misbehavior.


> It has not crashed yet with the patch though.

It seems that one of the tweks in this patch made the watchdog
act better than before.  So unless I hear from you (before the
start of next week) that some other message appears, or that your
oops re-appears, I'll submit some version of this patch for RC3.

And if you're up for it, I may have another patch for you
to try on top of this one ... I had an idea about IRQ trigger
modes that might be causing this problem.

- Dave