Re: annoying frequent overcurrent messages.

From: Ray Lee
Date: Wed Jul 12 2006 - 13:32:56 EST


On 7/12/06, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote:
On Wed, 12 Jul 2006, Ray Lee wrote:

> On 7/12/06, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote:
> > Dave Jones wrote:
> > > I have a box that's having its dmesg flooded with..
> > >
> > > hub 1-0:1.0: over-current change on port 1
> > > hub 1-0:1.0: over-current change on port 2
> > > hub 1-0:1.0: over-current change on port 1
> > > hub 1-0:1.0: over-current change on port 2
> > ...
> >
> > > over and over again..
> > > The thing is, this box doesn't even have any USB devices connected to it,
> > > so there's absolutely nothing I can do to remedy this.
> >
> > Since you're not using the UHCI controller on that computer, you could
> > simply rmmod uhci-hcd (or modify /etc/modprobe.conf to prevent it from
> > being loaded in the first place). That would stop the constant interrupts
> > and the syslog spamming.
>
> For the syslog spamming, you could jus emit the message once when the
> state is first noticed, then emit a everything good message when it
> clears up. There's no need to log it repeatedly during the problem
> period.

That's almost exactly how the driver behaves currently -- the message is
printed just once when the state is first noticed. Nothing is printed
when the state is cleared, and nothing gets printed repeatedly during the
problem period. But then the problem recurs very quickly.

Then the logging of the 'all cleared up' message would be better if it
had a bit of hysteresis to it -- the good state is noticed, but don't
log it as such until it hangs out there for a while and has had a
chance to quiesce.

Ray
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