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From: Ricardo Ribalda <ribalda@chromium.org>
Date: Wed, 27 Mar 2024 08:24:46 +0000
Subject: [PATCH v4 3/4] media: uvcvideo: Avoid race condition during
 unregister
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Message-Id: <20240327-guenter-mini-v4-3-49955c198eae@chromium.org>
References: <20240327-guenter-mini-v4-0-49955c198eae@chromium.org>
In-Reply-To: <20240327-guenter-mini-v4-0-49955c198eae@chromium.org>
To: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Guenter Roeck <linux@roeck-us.net>, Max Staudt <mstaudt@chromium.org>, 
 Tomasz Figa <tfiga@chromium.org>, 
 Laurent Pinchart <laurent.pinchart@ideasonboard.com>, 
 Alan Stern <stern@rowland.harvard.edu>, 
 Hans Verkuil <hverkuil-cisco@xs4all.nl>, linux-media@vger.kernel.org, 
 linux-kernel@vger.kernel.org, Sean Paul <seanpaul@chromium.org>, 
 Ricardo Ribalda <ribalda@chromium.org>, 
 Sakari Ailus <sakari.ailus@linux.intel.com>

The control events are handled asynchronously by the driver. Once the
control event are handled, the urb is re-submitted.

If we simply kill the urb, there is a chance that a control event is
waiting to be processed, which will re-submit the urb after the device is
disconnected.

uvc_status_suspend() flushes the async controls and stops the urb in a
correct manner.

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
 drivers/media/usb/uvc/uvc_status.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/usb/uvc/uvc_status.c b/drivers/media/usb/uvc/uvc_status.c
index 375a95dd30110..8fd8250110e2f 100644
--- a/drivers/media/usb/uvc/uvc_status.c
+++ b/drivers/media/usb/uvc/uvc_status.c
@@ -294,7 +294,7 @@ int uvc_status_init(struct uvc_device *dev)
 
 void uvc_status_unregister(struct uvc_device *dev)
 {
-	usb_kill_urb(dev->int_urb);
+	uvc_status_suspend(dev);
 	uvc_input_unregister(dev);
 }
 

-- 
2.44.0.396.g6e790dbe36-goog