From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Date: Wed, 26 Apr 2017 11:50:08 +0000 (+0900)
Subject: usb: gadget: udc: renesas_usb3: fix deadlock by spinlock
X-Git-Tag: archive/raspbian/4.9.30-2+deb9u2+rpi1~4^2~322
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=61facbdc99f183745b8484af415806a039a36184;p=linux-4.9.git

usb: gadget: udc: renesas_usb3: fix deadlock by spinlock

commit 067d6fdc558d2c43f0bfdc7af99630dd5eb08dc5 upstream.

This patch fixes an issue that this driver is possible to cause
deadlock by double-spinclocked in renesas_usb3_stop_controller().
So, this patch removes spinlock API calling in renesas_usb3_stop().
(In other words, the previous code had a redundant lock.)

Fixes: 746bfe63bba3 ("usb: gadget: renesas_usb3: add support for Renesas USB3.0 peripheral controller")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/usb/gadget/udc/renesas_usb3.c b/drivers/usb/gadget/udc/renesas_usb3.c
index 6be61139ce15..82e301e4da89 100644
--- a/drivers/usb/gadget/udc/renesas_usb3.c
+++ b/drivers/usb/gadget/udc/renesas_usb3.c
@@ -1718,14 +1718,11 @@ static int renesas_usb3_start(struct usb_gadget *gadget,
 static int renesas_usb3_stop(struct usb_gadget *gadget)
 {
 	struct renesas_usb3 *usb3 = gadget_to_renesas_usb3(gadget);
-	unsigned long flags;
 
-	spin_lock_irqsave(&usb3->lock, flags);
 	usb3->softconnect = false;
 	usb3->gadget.speed = USB_SPEED_UNKNOWN;
 	usb3->driver = NULL;
 	renesas_usb3_stop_controller(usb3);
-	spin_unlock_irqrestore(&usb3->lock, flags);
 
 	pm_runtime_put(usb3_to_dev(usb3));
 	pm_runtime_disable(usb3_to_dev(usb3));