Re: Linux 3.8-rc1 - another regression on USB :-(

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Sun, Dec 23, 2012 at 02:35:49PM -0800, Linus Torvalds wrote:
> Woody,
>  Any chance you can bisect this? It's not going to be hugely pleasant
> (with 11k+ commits in between 3.7 and 3.8-rc1 you'll have to compile
> and test at least 14 kernels), but it would help enormously. Of
> course, maybe some USB person can guess what would cause the device to
> go offline..
> 
> Added Greg and the linux-usb mailing list to the participants list:
> the images are in the original email on lkml, but there isn't anything
> particularly interesting there, it really just seems to be an
> unexpected and spurious USB disconnect, resulting in "USB disconnect,
> device number 2" followed by "Rejecting I/O to offline device".

I don't see any images on lkml, sorry.

The kernel log for when the disconnect happened would be great to get.

The kernel can't cause a device to disconnect, that's an electrical
thing usually, is this perchance a flaky device/connection?  Or has it
always worked on older kernels?

What host controller is being used here (xhci, ehci, etc.?)

thanks,

greg k-h