Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20220308022929.30002-1-linmq006@gmail.com>
In-Reply-To: <20220308022929.30002-1-linmq006@gmail.com>
From:   Rob Herring <robh@kernel.org>
Date:   Thu, 10 Mar 2022 13:06:15 -0600
Message-ID: <CAL_JsqKpr9ksR2gse4fHPHbNfv9+TtSu99+Ofz1mZ16WNjswYA@mail.gmail.com>
Subject: Re: [PATCH] PCI: imx6: Add missing of_node_put() in imx6_pcie_probe
To:     Miaoqian Lin <linmq006@gmail.com>
Cc:     Richard Zhu <hongxing.zhu@nxp.com>,
        Lucas Stach <l.stach@pengutronix.de>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        =?UTF-8?Q?Krzysztof_Wilczy=C5=84ski?= <kw@linux.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>,
        Trent Piepho <tpiepho@impinj.com>,
        PCI <linux-pci@vger.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Mon, Mar 7, 2022 at 8:29 PM Miaoqian Lin <linmq006@gmail.com> wrote:
>
> The device_node pointer is returned by of_parse_phandle()  with refcount
> incremented. We should use of_node_put() on it when done.
>
> Fixes: 1df82ec46600 ("PCI: imx: Add workaround for e10728, IMX7d PCIe PLL failure")
> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
> ---
>  drivers/pci/controller/dwc/pci-imx6.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 6974bd5aa116..bcc338ab6c11 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -1050,6 +1050,7 @@ static int imx6_pcie_probe(struct platform_device *pdev)
>                 struct resource res;
>
>                 ret = of_address_to_resource(np, 0, &res);
> +               of_node_put(np);

So now you are using the phy within the driver, but not holding a
reference to its node? That is wrong. Though if a struct device was
created for the phy's node, it would hold a reference. There are a
bunch of error paths where the reference should be dropped. But
really, this driver is a big mess with the phy binding and framework
not used and your nodes probably aren't going to be disappearing on
you anyways.

Rob