Subject: Re: [PATCH v2 6/6] drivers: remoteproc: Add Xilinx r5 remoteproc
 driver
To:     Tanmay Shah <tanmay.shah@xilinx.com>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
        Michal Simek <michal.simek@xilinx.com>
Cc:     Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Ben Levinsky <ben.levinsky@xilinx.com>,
        Bill Mills <bill.mills@linaro.org>,
        Sergei Korneichuk <sergei.korneichuk@xilinx.com>,
        linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org
References: <20211123062050.1442712-1-tanmay.shah@xilinx.com>
 <20211123062050.1442712-7-tanmay.shah@xilinx.com>
 <ab9e009a-5e35-ae49-2c8e-65be6ba36d7f@metafoo.de>
 <acbd7749-7bb2-0de2-5658-2b62ace9520a@xilinx.com>
From:   Lars-Peter Clausen <lars@metafoo.de>
Message-ID: <b8b24b65-786b-2a4e-5548-5e5e8bf988be@metafoo.de>
Date:   Mon, 13 Dec 2021 20:43:14 +0100
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On 12/13/21 8:31 PM, Tanmay Shah wrote:
>>> +static int zynqmp_r5_cluster_init(struct zynqmp_r5_cluster *cluster)
>>> +{
>>> [...]
>>> +
>>>
>>> +    i = 0;
>>> +    for_each_available_child_of_node(dev_node, child) {
>>> +        child_pdev = of_find_device_by_node(child);
>>> +        if (!child_pdev)
>> A return or a break in a for_each_available_child_of_node() will leak 
>> the reference to the child node.
>
> Do you mean I have to use of_put_node for each child?

You have to put a `of_put_node(child)` before each break or return in 
the loop.

If you search the kernel commit history for 
for_each_available_child_of_node or for_each_child_of_node you'll find 
many fixes for similar problems. For example 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e1b391e9712db