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Subject: Re: [PATCH] PCI: tegra: Fix runtime PM imbalance in
 pex_ep_event_pex_rst_deassert
To:     Dinghao Liu <dinghao.liu@zju.edu.cn>, <kjlu@umn.edu>
CC:     Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Rob Herring <robh@kernel.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        Vidya Sagar <vidyas@nvidia.com>,
        Jingoo Han <jingoohan1@gmail.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        <linux-pci@vger.kernel.org>, <linux-tegra@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <20210408072700.15791-1-dinghao.liu@zju.edu.cn>
From:   Jon Hunter <jonathanh@nvidia.com>
Message-ID: <11feff02-c466-5296-b4c3-85754c755c9a@nvidia.com>
Date:   Thu, 8 Apr 2021 13:34:37 +0100
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On 08/04/2021 08:26, Dinghao Liu wrote:
> pm_runtime_get_sync() will increase the runtime PM counter
> even it returns an error. Thus a pairing decrement is needed
> to prevent refcount leak. Fix this by replacing this API with
> pm_runtime_resume_and_get(), which will not change the runtime
> PM counter on error.
> 
> Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
> ---
>  drivers/pci/controller/dwc/pcie-tegra194.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
> index 6fa216e52d14..0e94190ca4e8 100644
> --- a/drivers/pci/controller/dwc/pcie-tegra194.c
> +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
> @@ -1645,7 +1645,7 @@ static void pex_ep_event_pex_rst_deassert(struct tegra_pcie_dw *pcie)
>  	if (pcie->ep_state == EP_STATE_ENABLED)
>  		return;
>  
> -	ret = pm_runtime_get_sync(dev);
> +	ret = pm_runtime_resume_and_get(dev);
>  	if (ret < 0) {
>  		dev_err(dev, "Failed to get runtime sync for PCIe dev: %d\n",
>  			ret);
> 

There are two places in the driver where pm_runtime_get_sync() is called.

Thanks
Jon

-- 
nvpublic