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Date: Fri, 31 Mar 2017 21:46:29 +0100
From: Russell King - ARM Linux <linux@armlinux.org.uk>
To: Hans Verkuil <hverkuil@xs4all.nl>
Cc: linux-media@vger.kernel.org,
        Daniel Vetter <daniel.vetter@intel.com>,
        dri-devel@lists.freedesktop.org, linux-samsung-soc@vger.kernel.org,
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        Benjamin Gaignard <benjamin.gaignard@linaro.org>,
        Patrice.chotard@st.com, Hans Verkuil <hans.verkuil@cisco.com>
Subject: Re: [PATCHv6 01/10] media: add CEC notifier support
Message-ID: <20170331204629.GV7909@n2100.armlinux.org.uk>
References: <20170331122036.55706-1-hverkuil@xs4all.nl>
 <20170331122036.55706-2-hverkuil@xs4all.nl>
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On Fri, Mar 31, 2017 at 02:20:27PM +0200, Hans Verkuil wrote:
> +struct cec_notifier *cec_notifier_get(struct device *dev)
> +{
> +	struct cec_notifier *n;
> +
> +	mutex_lock(&cec_notifiers_lock);
> +	list_for_each_entry(n, &cec_notifiers, head) {
> +		if (n->dev == dev) {
> +			mutex_unlock(&cec_notifiers_lock);
> +			kref_get(&n->kref);

Isn't this racy?  What stops one thread trying to get the notifier
while another thread puts the notifier?

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