Patch "usb: gadget: udc: renesas_usb3: Fix usb_gadget_giveback_request() calling" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

usb: gadget: udc: renesas_usb3: Fix usb_gadget_giveback_request() calling

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
usb-gadget-udc-renesas_usb3-fix-usb_gadget_giveback_request-calling.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Yoshihiro Shimoda <[email protected]>
Date: Wed, 2 Aug 2017 21:06:35 +0900
Subject: usb: gadget: udc: renesas_usb3: Fix usb_gadget_giveback_request() calling

From: Yoshihiro Shimoda <[email protected]>

commit aca5b9ebd096039657417c321a9252c696b359c2 upstream.

According to the gadget.h, a "complete" function will always be called with interrupts disabled. However, sometimes usb3_request_done() function is called with interrupts enabled. So, this function should be held by spin_lock_irqsave() to disable interruption. Also, this driver has to call spin_unlock() to avoid spinlock recursion by this driver before calling usb_gadget_giveback_request().

---
 drivers/usb/gadget/udc/renesas_usb3.c |   21 ++++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

@@ -685,21 +685,32 @@ static struct renesas_usb3_request *usb3
 	return usb3_req;
 }
 
-static void usb3_request_done(struct renesas_usb3_ep *usb3_ep,
-			      struct renesas_usb3_request *usb3_req, int status)
+static void __usb3_request_done(struct renesas_usb3_ep *usb3_ep,
+				struct renesas_usb3_request *usb3_req,
+				int status)
 {
 	struct renesas_usb3 *usb3 = usb3_ep_to_usb3(usb3_ep);
-	unsigned long flags;
 
 	dev_dbg(usb3_to_dev(usb3), "giveback: ep%2d, %u, %u, %d\n",
 		usb3_ep->num, usb3_req->req.length, usb3_req->req.actual,
 		status);
 	usb3_req->req.status = status;
-	spin_lock_irqsave(&usb3->lock, flags);
 	usb3_ep->started = false;
 	list_del_init(&usb3_req->queue);
-	spin_unlock_irqrestore(&usb3->lock, flags);
+	spin_unlock(&usb3->lock);
 	usb_gadget_giveback_request(&usb3_ep->ep, &usb3_req->req);
+	spin_lock(&usb3->lock);
+}
+
+static void usb3_request_done(struct renesas_usb3_ep *usb3_ep,
+			      struct renesas_usb3_request *usb3_req, int status)
+{
+	struct renesas_usb3 *usb3 = usb3_ep_to_usb3(usb3_ep);
+	unsigned long flags;
+
+	spin_lock_irqsave(&usb3->lock, flags);
+	__usb3_request_done(usb3_ep, usb3_req, status);
+	spin_unlock_irqrestore(&usb3->lock, flags);
 }
 
 static void usb3_irq_epc_pipe0_status_end(struct renesas_usb3 *usb3)

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/usb-renesas_usbhs-fix-ugctrl2-value-for-r-car-gen3.patch queue-4.9/usb-gadget-udc-renesas_usb3-fix-usb_gadget_giveback_request-calling.patch