Re: Logs being spammed with "Unable to enumerate USB device"

Re: Logs being spammed with "Unable to enumerate USB device"

[Robert Hancock]

Larry Finger wrote:
> At times, my logs are filled with multiple copies of the following
> message:
> 
> hub 4-0:1.0: unable to enumerate USB device on port 5
> 
> The output of lsusb is as follows:
> 
> Bus 003 Device 002: ID 04f2:b016 Chicony Electronics Co., Ltd
> Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
> Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
> Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
> Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
> 
> The hubs are built into an HP dv2815nr laptop, and nothing is plugged in.
> 
> I'm currently running v2.6.27-rc7 from the linux-2.6 git tree, but it
> does not seem to be a regression. In checking my back logs, my first
> such "storm" happened on July 25, with successive ones on September 8,
> 9, 12 and 21.
> 
> Is this an indication of hardware failure? What further info is
> required? Any suggestions for debugging code to try to pinpoint the
> problem?

Is this just occurring during bootup? I think this is normal if the EHCI 
driver is loaded after UHCI or OHCI because it causes the device to be 
switched away from the other controller that's trying to enumerate it, 
at least momentarily.

Re: Logs being spammed with "Unable to enumerate USB device"

[Larry Finger]

Robert Hancock wrote:
> 
> Is this just occurring during bootup? I think this is normal if the EHCI
> driver is loaded after UHCI or OHCI because it causes the device to be
> switched away from the other controller that's trying to enumerate it,
> at least momentarily.

It sometimes happens at bootup, but at other times I will get hundreds
of them in a row in the logs. I have put in some debugging where the
message is triggered, but have not seen any of the flood-type since.

Larry

Re: Logs being spammed with "Unable to enumerate USB device"

[Larry Finger]

Larry Finger wrote:
> Robert Hancock wrote:
>> Is this just occurring during bootup? I think this is normal if the EHCI
>> driver is loaded after UHCI or OHCI because it causes the device to be
>> switched away from the other controller that's trying to enumerate it,
>> at least momentarily.
> 
> It sometimes happens at bootup, but at other times I will get hundreds
> of them in a row in the logs. I have put in some debugging where the
> message is triggered, but have not seen any of the flood-type since.

I now have more information. The if statement that triggers the
message is as follows:

if (hub->hdev->parent ||
    !hcd->driver->port_handed_over ||
    !(hcd->driver->port_handed_over)(hcd, port1))

For all the messages that I have captured, the first condition
(hub->hdev->parent) is always true.

For the isolated message that occurs at bootup, the second condition
(!hcd->driver->port_handed_over) is true and the third is false.

When the message storm occurs, the second condition is false, i.e.
hcd->driver->port_handed_over is not zero, but
!(hcd->driver->port_handed_over)(hcd, port1) is true.

As before, I am willing to test any patches. As the message storm is
rare, it will be difficult to show that a patch fixes the problem.

Larry

Logs being spammed with "Unable to enumerate USB device"

[Larry Finger]

At times, my logs are filled with multiple copies of the following
message:

hub 4-0:1.0: unable to enumerate USB device on port 5

The output of lsusb is as follows:

Bus 003 Device 002: ID 04f2:b016 Chicony Electronics Co., Ltd
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

The hubs are built into an HP dv2815nr laptop, and nothing is plugged in.

I'm currently running v2.6.27-rc7 from the linux-2.6 git tree, but it
does not seem to be a regression. In checking my back logs, my first
such "storm" happened on July 25, with successive ones on September 8,
9, 12 and 21.

Is this an indication of hardware failure? What further info is
required? Any suggestions for debugging code to try to pinpoint the
problem?

Thanks,

Larry