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FAILED: patch "[PATCH] usb: dwc3: clear forceRM when issuing EndTransfer" failed to apply to 6.12-stable tree

PATCH New [email protected] 2 participants 3 messages Sep 8 – Sep 10

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#0 lore raw

The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x b58e6200450d350314db0ecda7d6d1bde3281e80
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026090819-kilometer-itunes-d755@gregkh' --subject-prefix 'PATCH 6.12.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From b58e6200450d350314db0ecda7d6d1bde3281e80 Mon Sep 17 00:00:00 2001
From: Elson Serrao <[email protected]>
Date: Thu, 13 Aug 2026 08:14:56 -0700
Subject: [PATCH] usb: dwc3: clear forceRM when issuing EndTransfer

The forceRM bit of the DEPCMD register controls the behavior of the EndTransfer command used to stop an active transfer. Older DWC3 programming guide revisions recommended setting forceRM=1 when issuing EndTransfer. Newer programming guide revisions recommend issuing EndTransfer with forceRM cleared.

With forceRM=1 on DWC_usb31 v2.00a and v2.10a controllers, a transfer aborted through the ep_dequeue path was observed to remain active after EndTransfer completion. A subsequent StartTransfer issued on the same endpoint triggered writes associated with the aborted transfer. This resulted in an SMMU fault because the transfer buffer had already been unmapped during EndTransfer command-completion cleanup.

Using forceRM=0 eliminates the issue. Although older DWC3 programming guide revisions recommended setting forceRM=1, no issues are known from using forceRM=0. Clear forceRM when issuing EndTransfer to provide consistent EndTransfer behavior and align with newer programming guide recommendations.

Fixes 1e43c86d84fb ("usb: dwc3: core: Add DWC31 version 2.00a controller")
Cc stable <[email protected]>
drivers/usb/dwc3/ep0.c +1 -1
index bfe616194dfa..310b5ffb236a 100644
@@ -304,7 +304,7 @@ void dwc3_ep0_out_start(struct dwc3 *dwc)
 
 		dwc3_ep->flags &= ~DWC3_EP_DELAY_STOP;
 		if (dwc->connected)
-			dwc3_stop_active_transfer(dwc3_ep, true, true);
+			dwc3_stop_active_transfer(dwc3_ep, false, true);
 		else
 			dwc3_remove_requests(dwc, dwc3_ep, -ESHUTDOWN);
 	}
drivers/usb/dwc3/gadget.c +13 -8
index fa944856f956..f245e66cd13d 100644
@@ -1004,7 +1004,7 @@ static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep, unsigned int action)
 			 * controller to generate an ERDY to initiate the
 			 * stream.
 			 */
-			dwc3_stop_active_transfer(dep, true, true);
+			dwc3_stop_active_transfer(dep, false, true);
 
 			/*
 			 * All stream eps will reinitiate stream on NoStream
@@ -1032,7 +1032,7 @@ void dwc3_remove_requests(struct dwc3 *dwc, struct dwc3_ep *dep, int status)
 {
 	struct dwc3_request		*req;
 
-	dwc3_stop_active_transfer(dep, true, false);
+	dwc3_stop_active_transfer(dep, false, false);
 
 	/* If endxfer is delayed, avoid unmapping requests */
 	if (dep->flags & DWC3_EP_DELAY_STOP)
@@ -1720,7 +1720,7 @@ static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep)
 		if (ret == -EAGAIN)
 			return ret;
 
-		dwc3_stop_active_transfer(dep, true, true);
+		dwc3_stop_active_transfer(dep, false, true);
 
 		list_for_each_entry_safe(req, tmp, &dep->started_list, list)
 			dwc3_gadget_move_cancelled_request(req, DWC3_REQUEST_STATUS_DEQUEUED);
@@ -1757,6 +1757,11 @@ static int __dwc3_gadget_get_frame(struct dwc3 *dwc)
  * the controller won't update the TRB progress on command
  * completion. It also won't clear the HWO bit in the TRB.
  * The command will also not complete immediately in that case.
+ *
+ * Older programming guide revisions recommended setting ForceRM to 1
+ * when ending a transfer. Newer programming guide revisions now
+ * recommend keeping ForceRM cleared, and TRBs are properly updated
+ * on command completion.
  */
 static int __dwc3_stop_active_transfer(struct dwc3_ep *dep, bool force, bool interrupt)
 {
@@ -1882,7 +1887,7 @@ static int dwc3_gadget_start_isoc_quirk(struct dwc3_ep *dep)
 		 * to wait for the next XferNotReady to test the command again
 		 */
 		if (cmd_status == 0) {
-			dwc3_stop_active_transfer(dep, true, true);
+			dwc3_stop_active_transfer(dep, false, true);
 			return 0;
 		}
 	}
@@ -2165,7 +2170,7 @@ static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
 			struct dwc3_request *t;
 
 			/* wait until it is processed */
-			dwc3_stop_active_transfer(dep, true, true);
+			dwc3_stop_active_transfer(dep, false, true);
 
 			/*
 			 * Remove any started request if the transfer is
@@ -2242,7 +2247,7 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
 			return 0;
 		}
 
-		dwc3_stop_active_transfer(dep, true, true);
+		dwc3_stop_active_transfer(dep, false, true);
 
 		list_for_each_entry_safe(req, tmp, &dep->started_list, list)
 			dwc3_gadget_move_cancelled_request(req, DWC3_REQUEST_STATUS_STALLED);
@@ -3368,7 +3373,7 @@ static void dwc3_nostream_work(struct work_struct *work)
 		dwc3_send_gadget_generic_command(dwc, cmd, dep->number);
 	} else {
 		dep->flags |= DWC3_EP_DELAY_START;
-		dwc3_stop_active_transfer(dep, true, true);
+		dwc3_stop_active_transfer(dep, false, true);
 		spin_unlock_irqrestore(&dwc->lock, flags);
 		return;
 	}
@@ -3726,7 +3731,7 @@ static bool dwc3_gadget_endpoint_trbs_complete(struct dwc3_ep *dep,
 	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);
+		dwc3_stop_active_transfer(dep, false, true);
 	else if (dwc3_gadget_ep_should_continue(dep))
 		if (__dwc3_gadget_kick_transfer(dep) == 0)
 			no_started_trb = false;
maintainer
#1 lore raw

PATCH 1/2 usb: dwc3: gadget: Reinitiate stream for all host NoStream behavior

From: Thinh Nguyen <[email protected]>

[ Upstream commit dcfe437492e27d54f3ac491aed024da760f5c43c ]

There are too many different host behaviors when it comes to NoStream handling, and not everyone follows the USB and xHCI spec. The DWC3 driver attempts to do some guess work to interop with different hosts, but it can't cover everything. Let's keep it simple and treat every host the same: just retry on NoStream after a 100ms of no response delay. Note that some hosts cannot handle frequent retries. This may affect performance on certain defective hosts, but NoStream is a rare occurrence and interoperability is more important.

Stable-dep-of: b58e6200450d ("usb: dwc3: clear forceRM when issuing EndTransfer")

---
 drivers/usb/dwc3/core.h   |   3 +-
 drivers/usb/dwc3/gadget.c | 109 ++++++++++++++++++++------------------
 2 files changed, 59 insertions(+), 53 deletions(-)
drivers/usb/dwc3/core.h +2 -1
index eb8b8f3e52167..7ee7228b31eb9 100644
@@ -742,6 +742,7 @@ struct dwc3_event_buffer {
  */
 struct dwc3_ep {
 	struct usb_ep		endpoint;
+	struct delayed_work	nostream_work;
 	struct list_head	cancelled_list;
 	struct list_head	pending_list;
 	struct list_head	started_list;
@@ -764,7 +765,7 @@ struct dwc3_ep {
 #define DWC3_EP_WAIT_TRANSFER_COMPLETE	BIT(7)
 #define DWC3_EP_IGNORE_NEXT_NOSTREAM	BIT(8)
 #define DWC3_EP_FORCE_RESTART_STREAM	BIT(9)
-#define DWC3_EP_FIRST_STREAM_PRIMED	BIT(10)
+#define DWC3_EP_STREAM_PRIMED		BIT(10)
 #define DWC3_EP_PENDING_CLEAR_STALL	BIT(11)
 #define DWC3_EP_TXFIFO_RESIZED		BIT(12)
 #define DWC3_EP_DELAY_STOP             BIT(13)
drivers/usb/dwc3/gadget.c +57 -52

143 lines not on this page · raw message

Signature · 1 line
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maintainer
#2 lore raw

PATCH 2/2 usb: dwc3: clear forceRM when issuing EndTransfer

From: Elson Serrao <[email protected]>

[ Upstream commit b58e6200450d350314db0ecda7d6d1bde3281e80 ]

The forceRM bit of the DEPCMD register controls the behavior of the EndTransfer command used to stop an active transfer. Older DWC3 programming guide revisions recommended setting forceRM=1 when issuing EndTransfer. Newer programming guide revisions recommend issuing EndTransfer with forceRM cleared.

With forceRM=1 on DWC_usb31 v2.00a and v2.10a controllers, a transfer aborted through the ep_dequeue path was observed to remain active after EndTransfer completion. A subsequent StartTransfer issued on the same endpoint triggered writes associated with the aborted transfer. This resulted in an SMMU fault because the transfer buffer had already been unmapped during EndTransfer command-completion cleanup.

Using forceRM=0 eliminates the issue. Although older DWC3 programming guide revisions recommended setting forceRM=1, no issues are known from using forceRM=0. Clear forceRM when issuing EndTransfer to provide consistent EndTransfer behavior and align with newer programming guide recommendations.

Fixes 1e43c86d84fb ("usb: dwc3: core: Add DWC31 version 2.00a controller")
Cc stable <[email protected]>
---
 drivers/usb/dwc3/ep0.c    |  2 +-
 drivers/usb/dwc3/gadget.c | 21 +++++++++++++--------
 2 files changed, 14 insertions(+), 9 deletions(-)
drivers/usb/dwc3/ep0.c +1 -1
index bcc9cc3980683..5e4f35e572659 100644
@@ -304,7 +304,7 @@ void dwc3_ep0_out_start(struct dwc3 *dwc)
 
 		dwc3_ep->flags &= ~DWC3_EP_DELAY_STOP;
 		if (dwc->connected)
-			dwc3_stop_active_transfer(dwc3_ep, true, true);
+			dwc3_stop_active_transfer(dwc3_ep, false, true);
 		else
 			dwc3_remove_requests(dwc, dwc3_ep, -ESHUTDOWN);
 	}
drivers/usb/dwc3/gadget.c +13 -8
index 3cf22447c0415..225bc433e3f83 100644
@@ -991,7 +991,7 @@ static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep, unsigned int action)
 			 * controller to generate an ERDY to initiate the
 			 * stream.
 			 */
-			dwc3_stop_active_transfer(dep, true, true);
+			dwc3_stop_active_transfer(dep, false, true);
 
 			/*
 			 * All stream eps will reinitiate stream on NoStream
@@ -1019,7 +1019,7 @@ void dwc3_remove_requests(struct dwc3 *dwc, struct dwc3_ep *dep, int status)
 {
 	struct dwc3_request		*req;
 
-	dwc3_stop_active_transfer(dep, true, false);
+	dwc3_stop_active_transfer(dep, false, false);
 
 	/* If endxfer is delayed, avoid unmapping requests */
 	if (dep->flags & DWC3_EP_DELAY_STOP)
@@ -1709,7 +1709,7 @@ static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep)
 		if (ret == -EAGAIN)
 			return ret;
 
-		dwc3_stop_active_transfer(dep, true, true);
+		dwc3_stop_active_transfer(dep, false, true);
 
 		list_for_each_entry_safe(req, tmp, &dep->started_list, list)
 			dwc3_gadget_move_cancelled_request(req, DWC3_REQUEST_STATUS_DEQUEUED);
@@ -1746,6 +1746,11 @@ static int __dwc3_gadget_get_frame(struct dwc3 *dwc)
  * the controller won't update the TRB progress on command
  * completion. It also won't clear the HWO bit in the TRB.
  * The command will also not complete immediately in that case.
+ *
+ * Older programming guide revisions recommended setting ForceRM to 1
+ * when ending a transfer. Newer programming guide revisions now
+ * recommend keeping ForceRM cleared, and TRBs are properly updated
+ * on command completion.
  */
 static int __dwc3_stop_active_transfer(struct dwc3_ep *dep, bool force, bool interrupt)
 {
@@ -1871,7 +1876,7 @@ static int dwc3_gadget_start_isoc_quirk(struct dwc3_ep *dep)
 		 * to wait for the next XferNotReady to test the command again
 		 */
 		if (cmd_status == 0) {
-			dwc3_stop_active_transfer(dep, true, true);
+			dwc3_stop_active_transfer(dep, false, true);
 			return 0;
 		}
 	}
@@ -2154,7 +2159,7 @@ static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
 			struct dwc3_request *t;
 
 			/* wait until it is processed */
-			dwc3_stop_active_transfer(dep, true, true);
+			dwc3_stop_active_transfer(dep, false, true);
 
 			/*
 			 * Remove any started request if the transfer is
@@ -2231,7 +2236,7 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
 			return 0;
 		}
 
-		dwc3_stop_active_transfer(dep, true, true);
+		dwc3_stop_active_transfer(dep, false, true);
 
 		list_for_each_entry_safe(req, tmp, &dep->started_list, list)
 			dwc3_gadget_move_cancelled_request(req, DWC3_REQUEST_STATUS_STALLED);
@@ -3343,7 +3348,7 @@ static void dwc3_nostream_work(struct work_struct *work)
 		dwc3_send_gadget_generic_command(dwc, cmd, dep->number);
 	} else {
 		dep->flags |= DWC3_EP_DELAY_START;
-		dwc3_stop_active_transfer(dep, true, true);
+		dwc3_stop_active_transfer(dep, false, true);
 		spin_unlock_irqrestore(&dwc->lock, flags);
 		return;
 	}
@@ -3687,7 +3692,7 @@ static bool dwc3_gadget_endpoint_trbs_complete(struct dwc3_ep *dep,
 	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);
+		dwc3_stop_active_transfer(dep, false, true);
 	else if (dwc3_gadget_ep_should_continue(dep))
 		if (__dwc3_gadget_kick_transfer(dep) == 0)
 			no_started_trb = false;
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