Re: [PATCH v2] vhci_hcd: USB port can get stuck in the disabled state

[Michael <msbroadf@gmail.com>]

You can pass through any bluetooth dongle (or xbox wireless dongle)
through usbip and it will cause this issue.

For example, here is one of my customers
https://www.virtualhere.com/comment/9432#comment-9432 with the issue.

The device is in the  VDEV_ST_USED state when a reset occurs and so
its never re-enabled

Furthermore there is a bug in the line pr_err("vhci_device speed not set\n");
(L479) because resetting a full-speed device is not an error.


 On Thu, 22 Jul 2021 at 11:26, Shuah Khan <skhan@linuxfoundation.org> wrote:
>
> On 7/21/21 5:55 PM, Michael Broadfoot wrote:
> > When a remote usb device is attached to the local Virtual USB
> > Host Controller Root Hub port, the bound device driver may send a
> > port reset command. For example to initialize firmware (eg. btusb does this).
> > This port reset command can be sent at any time, however the VHCI hcd
> > root hub is only expecting reset to occur before the device receives
> > SET_ADDRESS. The USB port should always be enabled after a reset
> > (because the port is virtual and there is no possibility of hardware errors)
> >
> >
> >
> > Signed-off-by: Michael Broadfoot <msbroadf@gmail.com>
> > ---
> >   drivers/usb/usbip/vhci_hcd.c | 13 ++++---------
> >   1 file changed, 4 insertions(+), 9 deletions(-)
> >
> > diff --git a/drivers/usb/usbip/vhci_hcd.c b/drivers/usb/usbip/vhci_hcd.c
> > index 4ba6bcdaa8e9..d3cda1b2c15a 100644
> > --- a/drivers/usb/usbip/vhci_hcd.c
> > +++ b/drivers/usb/usbip/vhci_hcd.c
> > @@ -455,15 +455,10 @@ static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
> >                       vhci_hcd->port_status[rhport] &= ~(1 << USB_PORT_FEAT_RESET);
> >                       vhci_hcd->re_timeout = 0;
> >
> > -                     if (vhci_hcd->vdev[rhport].ud.status ==
> > -                         VDEV_ST_NOTASSIGNED) {
> > -                             usbip_dbg_vhci_rh(
> > -                                     " enable rhport %d (status %u)\n",
> > -                                     rhport,
> > -                                     vhci_hcd->vdev[rhport].ud.status);
> > -                             vhci_hcd->port_status[rhport] |=
> > -                                     USB_PORT_STAT_ENABLE;
> > -                     }
>
> VDEV_ST_NOTASSIGNED status indicates that the vdev is in use without
> address assigned - in other words port is initializing.
>
> This is part of the attach request handling when user requests to
> attach to a remote device. attach_store() will change the status
> to VDEV_ST_NOTASSIGNED and then initiate port_connect sequence.
>
> We don't want to touch the vdev when it is in other states.
>
> > +                     usbip_dbg_vhci_rh(" enable rhport %d (status %u)\n",
> > +                                       rhport,
> > +                                       vhci_hcd->vdev[rhport].ud.status);
> > +                     vhci_hcd->port_status[rhport] |= USB_PORT_STAT_ENABLE;
> >
> >                       if (hcd->speed < HCD_USB3) {
> >                               switch (vhci_hcd->vdev[rhport].speed) {
> >
>
> How did you find this problem? Does the port get into stuck state
> while attaching to a remote usbip device on the host?
>
> thanks,
> -- Shuah