Re: [PATCH 1/7] Revert "usb/uas: make sure data urb is gone if we receive status before that"

[Greg KH <gregkh@linuxfoundation.org>]

On Tue, Jun 19, 2012 at 09:54:48AM +0200, Gerd Hoffmann wrote:
> This reverts commit e4d8318a85779b25b880187b1b1c44e797bd7d4b.
> 
> This patch makes uas.c call usb_unlink_urb on data urbs.  The data urbs
> get freed in the completion callback.  This is illegal according to the
> usb_unlink_urb documentation.
> 
> This patch also makes the code expect the data completion callback
> being called before the status completion callback.  This isn't
> guaranteed to be the case, even though the actual data transfer should
> be finished by the time the status is received.
> 
> Background:  The ehci irq handler for example only know that there are
> finished transfers, it then has go check the QHs & TDs to see which
> transfers did actually finish.  It has no way to figure in which order
> the transfers did complete.  The xhci driver can call the callbacks in
> completion order thanks to the event queue.  This does nicely explain
> why the driver is solid on a (usb2) xhci port whereas it goes crazy on
> ehci in my testing.
> 
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---

Should this revert also go into 3.4-stable so that the device will work
properly on ehci?

thanks,

greg k-h