On Wed, Mar 29, 2023, Krishna Kurapati PSSNV wrote: > > > On 3/29/2023 2:50 AM, Thinh Nguyen wrote: > > Hi, > > > > On Tue, Mar 28, 2023, Krishna Kurapati wrote: > > > If the core soft reset timeout happens, avoid setting up event > > > buffers and starting gadget as the writes to these registers > > > may not reflect when in reset and setting the run stop bit > > > can lead the controller to access wrong event buffer address > > > resulting in a crash. > > > > > > Signed-off-by: Krishna Kurapati <quic_kriskura@xxxxxxxxxxx> > > > --- > > > drivers/usb/dwc3/gadget.c | 5 ++++- > > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c > > > index 3c63fa97a680..f0472801d9a5 100644 > > > --- a/drivers/usb/dwc3/gadget.c > > > +++ b/drivers/usb/dwc3/gadget.c > > > @@ -2620,13 +2620,16 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on) > > > * device-initiated disconnect requires a core soft reset > > > * (DCTL.CSftRst) before enabling the run/stop bit. > > > */ > > > - dwc3_core_soft_reset(dwc); > > > + ret = dwc3_core_soft_reset(dwc); > > > + if (ret) > > > + goto done; > > > dwc3_event_buffers_setup(dwc); > > > __dwc3_gadget_start(dwc); > > > ret = dwc3_gadget_run_stop(dwc, true, false); > > > } > > > +done: > > > pm_runtime_put(dwc->dev); > > > return ret; > > > -- > > > 2.40.0 > > > > > > > I think there's one more place that may needs this check. Can you also > > add this check in __dwc3_set_mode()? > > Hi Thinh, > > Sure. Will do it. > Will the below be good enough ? Or would it be good to add an error/warn log > there> There's already a warning message in dwc3_core_soft_reset() if it fails. > > kriskura@hu-kriskura-hyd:/local/mnt/workspace/krishna/skales2/skales/kernel$ > git diff drivers/usb/ > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > index 476b63618511..8d1d213d1dcd 100644 > --- a/drivers/usb/dwc3/core.c > +++ b/drivers/usb/dwc3/core.c > @@ -210,7 +210,9 @@ static void __dwc3_set_mode(struct work_struct *work) > } > break; > case DWC3_GCTL_PRTCAP_DEVICE: > - dwc3_core_soft_reset(dwc); > + ret = dwc3_core_soft_reset(dwc); > + if (ret) > + goto out; > > dwc3_event_buffers_setup(dwc); > If soft-reset failed, the controller is in a bad state. We should not perform any further operation until the next hard reset. We should flag the controller as dead. I don't think we have the equivalent of the host's HCD_FLAG_DEAD. It may require some work in the UDC core. Perhaps we can flag within dwc3 for now and prevent any further operation for a simpler fix. Thanks, Thinh
