| Message ID | 20201022005505.24167-3-peter.chen@nxp.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | usb: cdns3: three bug fixes for v5.10 | expand |
Peter Chen <peter.chen@nxp.com> writes: > When the system goes to suspend, if the controller is at device mode with > cable connecting to host, the call stack is: cdns3_suspend-> > cdns3_gadget_suspend -> cdns3_disconnect_gadget, after cdns3_disconnect_gadget > is called, it owns lock wrongly, it causes the system being deadlock after > resume due to at cdns3_device_thread_irq_handler, it tries to get the lock, > but can't get it forever. > > To fix it, we delete the unlock-lock operations at cdns3_disconnect_gadget, > and do it at the caller. > > Fixes: b1234e3b3b26 ("usb: cdns3: add runtime PM support") > Signed-off-by: Peter Chen <peter.chen@nxp.com> comment from previous thread is still valid. Missing __releases() and __acquires() annotation.
On 20-10-27 11:26:56, Felipe Balbi wrote: > Peter Chen <peter.chen@nxp.com> writes: > > > When the system goes to suspend, if the controller is at device mode with > > cable connecting to host, the call stack is: cdns3_suspend-> > > cdns3_gadget_suspend -> cdns3_disconnect_gadget, after cdns3_disconnect_gadget > > is called, it owns lock wrongly, it causes the system being deadlock after > > resume due to at cdns3_device_thread_irq_handler, it tries to get the lock, > > but can't get it forever. > > > > To fix it, we delete the unlock-lock operations at cdns3_disconnect_gadget, > > and do it at the caller. > > > > Fixes: b1234e3b3b26 ("usb: cdns3: add runtime PM support") > > Signed-off-by: Peter Chen <peter.chen@nxp.com> > > comment from previous thread is still valid. Missing __releases() and > __acquires() annotation. > Thanks, will add __must_hold sparse checker
diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c index 6ff3aa3db497..c127af6c0fe8 100644 --- a/drivers/usb/cdns3/gadget.c +++ b/drivers/usb/cdns3/gadget.c @@ -1744,11 +1744,8 @@ static int cdns3_check_ep_interrupt_proceed(struct cdns3_endpoint *priv_ep) static void cdns3_disconnect_gadget(struct cdns3_device *priv_dev) { - if (priv_dev->gadget_driver && priv_dev->gadget_driver->disconnect) { - spin_unlock(&priv_dev->lock); + if (priv_dev->gadget_driver && priv_dev->gadget_driver->disconnect) priv_dev->gadget_driver->disconnect(&priv_dev->gadget); - spin_lock(&priv_dev->lock); - } } /** @@ -1783,7 +1780,9 @@ static void cdns3_check_usb_interrupt_proceed(struct cdns3_device *priv_dev, /* Disconnection detected */ if (usb_ists & (USB_ISTS_DIS2I | USB_ISTS_DISI)) { + spin_unlock(&priv_dev->lock); cdns3_disconnect_gadget(priv_dev); + spin_lock(&priv_dev->lock); priv_dev->gadget.speed = USB_SPEED_UNKNOWN; usb_gadget_set_state(&priv_dev->gadget, USB_STATE_NOTATTACHED); cdns3_hw_reset_eps_config(priv_dev); @@ -3266,7 +3265,9 @@ static int cdns3_gadget_suspend(struct cdns3 *cdns, bool do_wakeup) { struct cdns3_device *priv_dev = cdns->gadget_dev; + spin_unlock(&cdns->lock); cdns3_disconnect_gadget(priv_dev); + spin_lock(&cdns->lock); priv_dev->gadget.speed = USB_SPEED_UNKNOWN; usb_gadget_set_state(&priv_dev->gadget, USB_STATE_NOTATTACHED);
When the system goes to suspend, if the controller is at device mode with cable connecting to host, the call stack is: cdns3_suspend-> cdns3_gadget_suspend -> cdns3_disconnect_gadget, after cdns3_disconnect_gadget is called, it owns lock wrongly, it causes the system being deadlock after resume due to at cdns3_device_thread_irq_handler, it tries to get the lock, but can't get it forever. To fix it, we delete the unlock-lock operations at cdns3_disconnect_gadget, and do it at the caller. Fixes: b1234e3b3b26 ("usb: cdns3: add runtime PM support") Signed-off-by: Peter Chen <peter.chen@nxp.com> --- drivers/usb/cdns3/gadget.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)