To reproduce the lock up do the following - connect otg host adapter and a USB device to the dual-role port so that it is in host mode. - suspend to mem. - disconnect otg adapter. - resume the system.

If we call dwc3_host_exit() before tasks are thawed xhci_plat_remove() seems to lock up at the second usb_remove_hcd() call.

To work around this we queue the _dwc3_set_mode() work on the system_freezable_wq.

Fixes: 41ce1456e1db ("usb: dwc3: core: make dwc3_set_mode() work properly") Cc: stable@vger.kernel.org # v4.12+ Suggested-by: Manu Gautam mgautam@codeaurora.org Signed-off-by: Roger Quadros rogerq@ti.com --- drivers/usb/dwc3/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index f1d838a..e94bf91 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -175,7 +175,7 @@ void dwc3_set_mode(struct dwc3 *dwc, u32 mode) dwc->desired_dr_role = mode; spin_unlock_irqrestore(&dwc->lock, flags);

- queue_work(system_power_efficient_wq, &dwc->drd_work); + queue_work(system_freezable_wq, &dwc->drd_work); }

u32 dwc3_core_fifo_space(struct dwc3_ep *dep, u8 type)