summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorThinh Nguyen <Thinh.Nguyen@synopsys.com>2024-11-14 01:02:12 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2024-12-09 10:32:53 +0100
commitbb6bf24fe03bd77f126eea4745a4e0098ef62543 (patch)
tree5a0601b0cb58fe4153b9c3b1733214d8a225cc96
parent5906ee3693674d734177df13a519a21bb03f730d (diff)
usb: dwc3: gadget: Fix checking for number of TRBs left
commit 02a6982b0ccfcdc39e20016f5fc9a1b7826a6ee7 upstream. The check whether the TRB ring is full or empty in dwc3_calc_trbs_left() is insufficient. It assumes there are active TRBs if there's any request in the started_list. However, that's not the case for requests with a large SG list. That is, if we have a single usb request that requires more TRBs than the total TRBs in the TRB ring, the queued TRBs will be available when all the TRBs in the ring are completed. But the request is only partially completed and remains in the started_list. With the current logic, the TRB ring is empty, but dwc3_calc_trbs_left() returns 0. Fix this by additionally checking for the request->num_trbs for active TRB count. Cc: stable@vger.kernel.org Fixes: 51f1954ad853 ("usb: dwc3: gadget: Fix dwc3_calc_trbs_left()") Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com> Link: https://lore.kernel.org/r/708dc62b56b77da1f704cc2ae9b6ddb1f2dbef1f.1731545781.git.Thinh.Nguyen@synopsys.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/usb/dwc3/gadget.c9
1 files changed, 6 insertions, 3 deletions
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 867000cdeb96..cbbffb785ee1 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1196,11 +1196,14 @@ static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep)
* pending to be processed by the driver.
*/
if (dep->trb_enqueue == dep->trb_dequeue) {
+ struct dwc3_request *req;
+
/*
- * If there is any request remained in the started_list at
- * this point, that means there is no TRB available.
+ * If there is any request remained in the started_list with
+ * active TRBs at this point, then there is no TRB available.
*/
- if (!list_empty(&dep->started_list))
+ req = next_request(&dep->started_list);
+ if (req && req->num_trbs)
return 0;
return DWC3_TRB_NUM - 1;