[PATCH v3 2/6] usb: dwc3: gadget: cancel requests instead of release after missed isoc

Dan Vacura
2022-10-17T20:55:35Z

From: Jeff Vanhoof <qjv001@motorola.com>

arm-smmu related crashes seen after a Missed ISOC interrupt when
no_interrupt=1 is used. This can happen if the hardware is still using
the data associated with a TRB after the usb_request's ->complete call
has been made. Instead of immediately releasing a request when a Missed
ISOC interrupt has occurred, this change will add logic to cancel the
request instead where it will eventually be released when the
END_TRANSFER command has completed. This logic is similar to some of the
cleanup done in dwc3_gadget_ep_dequeue.

Fixes: 6d8a019614f3 ("usb: dwc3: gadget: check for Missed Isoc from event status")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jeff Vanhoof <qjv001@motorola.com>
Co-developed-by: Dan Vacura <w36195@motorola.com>
Signed-off-by: Dan Vacura <w36195@motorola.com>
---
V1 -> V3:
- no change, new patch in series

drivers/usb/dwc3/core.h | 1 +
drivers/usb/dwc3/gadget.c | 38 ++++++++++++++++++++++++++------------
2 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 8f9959ba9fd4..9b005d912241 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -943,6 +943,7 @@ struct dwc3_request {
#define DWC3_REQUEST_STATUS_DEQUEUED 3
#define DWC3_REQUEST_STATUS_STALLED 4
#define DWC3_REQUEST_STATUS_COMPLETED 5
+#define DWC3_REQUEST_STATUS_MISSED_ISOC 6
#define DWC3_REQUEST_STATUS_UNKNOWN -1

u8 epnum;
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 079cd333632e..411532c5c378 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2021,6 +2021,9 @@ static void dwc3_gadget_ep_cleanup_cancelled_requests(struct dwc3_ep *dep)
case DWC3_REQUEST_STATUS_STALLED:
dwc3_gadget_giveback(dep, req, -EPIPE);
break;
+ case DWC3_REQUEST_STATUS_MISSED_ISOC:
+ dwc3_gadget_giveback(dep, req, -EXDEV);
+ break;
default:
dev_err(dwc->dev, "request cancelled with wrong reason:%d\n", req->status);
dwc3_gadget_giveback(dep, req, -ECONNRESET);
@@ -3402,21 +3405,32 @@ static bool dwc3_gadget_endpoint_trbs_complete(struct dwc3_ep *dep,
struct dwc3 *dwc = dep->dwc;
bool no_started_trb = true;

- dwc3_gadget_ep_cleanup_completed_requests(dep, event, status);
+ if (status == -EXDEV) {
+ struct dwc3_request *tmp;
+ struct dwc3_request *req;

- if (dep->flags & DWC3_EP_END_TRANSFER_PENDING)
- goto out;
+ if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING))
+ dwc3_stop_active_transfer(dep, true, true);

- if (!dep->endpoint.desc)
- return no_started_trb;
+ list_for_each_entry_safe(req, tmp, &dep->started_list, list)
+ dwc3_gadget_move_cancelled_request(req,
+ DWC3_REQUEST_STATUS_MISSED_ISOC);
+ } else {
+ dwc3_gadget_ep_cleanup_completed_requests(dep, event, status);

- if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
- list_empty(&dep->started_list) &&
- (list_empty(&dep->pending_list) || status == -EXDEV))
- dwc3_stop_active_transfer(dep, true, true);
- else if (dwc3_gadget_ep_should_continue(dep))
- if (__dwc3_gadget_kick_transfer(dep) == 0)
- no_started_trb = false;
+ if (dep->flags & DWC3_EP_END_TRANSFER_PENDING)
+ goto out;
+
+ if (!dep->endpoint.desc)
+ return no_started_trb;
+
+ if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
+ list_empty(&dep->started_list) && list_empty(&dep->pending_list))
+ dwc3_stop_active_transfer(dep, true, true);
+ else if (dwc3_gadget_ep_should_continue(dep))
+ if (__dwc3_gadget_kick_transfer(dep) == 0)
+ no_started_trb = false;
+ }

out:
/*
--
2.34.1