[PATCH 6.9 18/25] Revert "media: v4l2-ctrls: show all owned controls in log_status"

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6.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>

commit eba63df7eb1f95df6bfb67722a35372b6994928d upstream.

This reverts commit 9801b5b28c6929139d6fceeee8d739cc67bb2739.

This patch introduced a potential deadlock scenario:

[Wed May  8 10:02:06 2024]  Possible unsafe locking scenario:

[Wed May  8 10:02:06 2024]        CPU0                    CPU1
[Wed May  8 10:02:06 2024]        ----                    ----
[Wed May  8 10:02:06 2024]   lock(vivid_ctrls:1620:(hdl_vid_cap)->_lock);
[Wed May  8 10:02:06 2024]                                lock(vivid_ctrls:1608:(hdl_user_vid)->_lock);
[Wed May  8 10:02:06 2024]                                lock(vivid_ctrls:1620:(hdl_vid_cap)->_lock);
[Wed May  8 10:02:06 2024]   lock(vivid_ctrls:1608:(hdl_user_vid)->_lock);

For now just revert.

Fixes: 9801b5b28c69 ("media: v4l2-ctrls: show all owned controls in log_status")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/media/v4l2-core/v4l2-ctrls-core.c |   18 +++++-------------
 1 file changed, 5 insertions(+), 13 deletions(-)

--- a/drivers/media/v4l2-core/v4l2-ctrls-core.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls-core.c
@@ -2504,8 +2504,7 @@ int v4l2_ctrl_handler_setup(struct v4l2_
 EXPORT_SYMBOL(v4l2_ctrl_handler_setup);
 
 /* Log the control name and value */
-static void log_ctrl(const struct v4l2_ctrl_handler *hdl,
-		     struct v4l2_ctrl *ctrl,
+static void log_ctrl(const struct v4l2_ctrl *ctrl,
 		     const char *prefix, const char *colon)
 {
 	if (ctrl->flags & (V4L2_CTRL_FLAG_DISABLED | V4L2_CTRL_FLAG_WRITE_ONLY))
@@ -2515,11 +2514,7 @@ static void log_ctrl(const struct v4l2_c
 
 	pr_info("%s%s%s: ", prefix, colon, ctrl->name);
 
-	if (ctrl->handler != hdl)
-		v4l2_ctrl_lock(ctrl);
 	ctrl->type_ops->log(ctrl);
-	if (ctrl->handler != hdl)
-		v4l2_ctrl_unlock(ctrl);
 
 	if (ctrl->flags & (V4L2_CTRL_FLAG_INACTIVE |
 			   V4L2_CTRL_FLAG_GRABBED |
@@ -2538,7 +2533,7 @@ static void log_ctrl(const struct v4l2_c
 void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl,
 				  const char *prefix)
 {
-	struct v4l2_ctrl_ref *ref;
+	struct v4l2_ctrl *ctrl;
 	const char *colon = "";
 	int len;
 
@@ -2550,12 +2545,9 @@ void v4l2_ctrl_handler_log_status(struct
 	if (len && prefix[len - 1] != ' ')
 		colon = ": ";
 	mutex_lock(hdl->lock);
-	list_for_each_entry(ref, &hdl->ctrl_refs, node) {
-		if (ref->from_other_dev ||
-		    (ref->ctrl->flags & V4L2_CTRL_FLAG_DISABLED))
-			continue;
-		log_ctrl(hdl, ref->ctrl, prefix, colon);
-	}
+	list_for_each_entry(ctrl, &hdl->ctrls, node)
+		if (!(ctrl->flags & V4L2_CTRL_FLAG_DISABLED))
+			log_ctrl(ctrl, prefix, colon);
 	mutex_unlock(hdl->lock);
 }
 EXPORT_SYMBOL(v4l2_ctrl_handler_log_status);






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