On Thu, Aug 04, 2022 at 05:09:56PM +0200, Johan Hovold wrote: > The Qualcomm dwc3 runtime-PM implementation checks the xhci > platform-device pointer in the wakeup-interrupt handler to determine > whether the controller is in host mode and if so triggers a resume. > > After a role switch in OTG mode the xhci platform-device would have been > freed and the next wakeup from runtime suspend would access the freed > memory. > > Note that role switching is executed from a freezable workqueue, which > guarantees that the pointer is stable during suspend. > > Also note that runtime PM has been broken since commit 2664deb09306 > ("usb: dwc3: qcom: Honor wakeup enabled/disabled state"), which > incidentally also prevents this issue from being triggered. > > Fixes: a4333c3a6ba9 ("usb: dwc3: Add Qualcomm DWC3 glue driver") > Cc: stable@xxxxxxxxxxxxxxx # 4.18 > Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx> Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>