usb: dwc3: gadget: early giveback if End Transfer already completed (9f45581f) · Commits · 戴 / test

There is a rare race condition that may happen during a Disconnect Interrupt if we have a started request that happens to be dequeued *after* completion of End Transfer command. If that happens, that request will be left waiting for completion of an End Transfer command that will never happen. If End Transfer command has already completed before, we are safe to giveback the request straight away. Tested-by:

Thinh Nguyen <thinhn@synopsys.com> Signed-off-by:

Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/dwc3/gadget.c

+5 −1

Original line number	Original line	Diff line number	Diff line
	@@ -1550,7 +1550,10 @@ static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
	goto out0;		goto out0;

	dwc3_gadget_move_cancelled_request(req);		dwc3_gadget_move_cancelled_request(req);
			if (dep->flags & DWC3_EP_TRANSFER_STARTED)
	goto out0;		goto out0;
			else
			goto out1;
	}		}
	dev_err(dwc->dev, "request %pK was not queued to %s\n",		dev_err(dwc->dev, "request %pK was not queued to %s\n",
	request, ep->name);		request, ep->name);
	@@ -1558,6 +1561,7 @@ static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
	goto out0;		goto out0;
	}		}

			out1:
	dwc3_gadget_giveback(dep, req, -ECONNRESET);		dwc3_gadget_giveback(dep, req, -ECONNRESET);

	out0:		out0:

Admin message