Re: USB-related instability on 2.6.23-rc1

[Greg KH <greg@kroah.com>]

On Tue, Jul 31, 2007 at 03:06:07PM -0600, Grant Likely wrote:
> I've observed instability on my Macbook c2d with the Linus' latest
> tree.  Symptom is that USB devices start behaving badly and the kernel
> seems to be registering incorrect HID events; (ie. moving the mouse
> causes odd keyboard events).  If I continue to attempt to use the
> mouse, it results in a system freeze (and I don't see any kind of
> backtrace in /var/log/kern.log).  To reproduce the problem, I just
> need to be using the keyboard/mouse.  If I leave the system idle, the
> problem does not seem to occur.  If I actively use the keyboard/mouse,
> the problem can occur at any time; usually within 5-10 minutes.
> 
> In my particular case, I've got both a USB key/mouse pair on the
> laptop and an external key/mouse pair plugged in via a hub.
> Typically, it's the external mouse that exhibits badness first.
> 
> USB HID devices are definitely affected.  I have not tested USB block
> devices.  Isochronous transfers to a USB headset appear to be
> unaffected, but that's under minimal testing.
> 
> I've bisected down to commit 196705c9bbc03540429b0f7cf9ee35c2f928a534,
> "USB: EHCI cpufreq fix"
> 
> Reverting the patch at the head of the tree makes the kernel stable again.
> 
> I've attached my kernel config file and a dmesg output

Can you enable CONFIG_USB_DEBUG and send the linux-usb-devel list and
us, the output when you have these problems?

thanks,

greg k-h