Re: [PATCH v4] PCI: imx6: fix resource leaks in probe error paths

[Frank Li <Frank.li@oss.nxp.com>]

On Mon, Aug 24, 2026 at 11:04:54PM +0800, Zhijian Han wrote:
> [You don't often get email from hanzhijian1991@gmail.com. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
>
> imx_pcie_probe() leaks both pwrctrl devices and power domains on failure:
>
> - imx_pcie_attach_pd() attaches the "pcie" and "pcie_phy" power domains
>   and adds device links to them, but nothing detaches the domains on
>   probe failure or deferral, so they leak.
>
> - A failure of devm_pm_runtime_set_active_enabled() returns directly
>   without destroying the pwrctrl devices.
>
> - A partial failure inside imx_pcie_attach_pd() leaks the power domains
>   that were already attached.
>
> Add imx_pcie_detach_pd() to detach the power domains in reverse order of
> acquisition and call it from the probe error paths.  Add
> DL_FLAG_AUTOREMOVE_CONSUMER to the device links so the driver core
> removes them automatically when probe fails, instead of tracking and
> deleting them manually.
>
> Reported-by: sashiko-bot@kernel.org
> Link: https://lore.kernel.org/all/20260822013640.182C01F000E9@smtp.kernel.org/
> Fixes: 2c5768344f88 ("PCI: imx6: Move pci_pwrctrl_create_devices() to imx_pcie_probe()")
> Signed-off-by: Zhijian Han <hanzhijian1991@gmail.com>
> ---
> Changes in v4:
> - Use DL_FLAG_AUTOREMOVE_CONSUMER so the driver core removes the device
>   links automatically, instead of tracking and deleting them manually
> - Add a Fixes tag
>
>  drivers/pci/controller/dwc/pci-imx6.c | 37 +++++++++++++++++++++------
>  1 file changed, 29 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 39790e66b..0b4209365 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -639,6 +639,18 @@ static int imx6q_pcie_abort_handler(unsigned long addr,
>  }
>  #endif
>
> +static void imx_pcie_detach_pd(struct imx_pcie *imx_pcie)
> +{
> +       if (!IS_ERR_OR_NULL(imx_pcie->pd_pcie_phy)) {
> +               dev_pm_domain_detach(imx_pcie->pd_pcie_phy, true);
> +               imx_pcie->pd_pcie_phy = NULL;
> +       }
> +       if (!IS_ERR_OR_NULL(imx_pcie->pd_pcie)) {
> +               dev_pm_domain_detach(imx_pcie->pd_pcie, true);
> +               imx_pcie->pd_pcie = NULL;
> +       }
> +}
> +
>  static int imx_pcie_attach_pd(struct device *dev)
>  {
>         struct imx_pcie *imx_pcie = dev_get_drvdata(dev);
> @@ -655,24 +667,30 @@ static int imx_pcie_attach_pd(struct device *dev)
>         if (!imx_pcie->pd_pcie)
>                 return 0;
>         link = device_link_add(dev, imx_pcie->pd_pcie,
> -                       DL_FLAG_STATELESS |
>                         DL_FLAG_PM_RUNTIME |
> -                       DL_FLAG_RPM_ACTIVE);
> +                       DL_FLAG_RPM_ACTIVE |
> +                       DL_FLAG_AUTOREMOVE_CONSUMER);
>         if (!link) {
>                 dev_err(dev, "Failed to add device_link to pcie pd\n");
> +               imx_pcie_detach_pd(imx_pcie);
>                 return -EINVAL;
>         }
>
>         imx_pcie->pd_pcie_phy = dev_pm_domain_attach_by_name(dev, "pcie_phy");
> -       if (IS_ERR(imx_pcie->pd_pcie_phy))
> -               return PTR_ERR(imx_pcie->pd_pcie_phy);
> +       if (IS_ERR(imx_pcie->pd_pcie_phy)) {
> +               int ret = PTR_ERR(imx_pcie->pd_pcie_phy);
> +
> +               imx_pcie_detach_pd(imx_pcie);
> +               return ret;
> +       }
>
>         link = device_link_add(dev, imx_pcie->pd_pcie_phy,
> -                       DL_FLAG_STATELESS |
>                         DL_FLAG_PM_RUNTIME |
> -                       DL_FLAG_RPM_ACTIVE);
> +                       DL_FLAG_RPM_ACTIVE |
> +                       DL_FLAG_AUTOREMOVE_CONSUMER);
>         if (!link) {
>                 dev_err(dev, "Failed to add device_link to pcie_phy pd\n");
> +               imx_pcie_detach_pd(imx_pcie);
>                 return -EINVAL;
>         }
>
> @@ -1956,8 +1974,10 @@ static int imx_pcie_probe(struct platform_device *pdev)
>                 return ret;
>
>         ret = pci_pwrctrl_create_devices(dev);
> -       if (ret)
> +       if (ret) {
> +               imx_pcie_detach_pd(imx_pcie);

use devm_add_action_or_reset() to do tear down.

Frank

>                 return dev_err_probe(dev, ret, "failed to create pwrctrl devices\n");
> +       }
>
>         pci->use_parent_dt_ranges = true;
>         if (imx_pcie->drvdata->mode == DW_PCIE_EP_TYPE) {
> @@ -1975,7 +1995,7 @@ static int imx_pcie_probe(struct platform_device *pdev)
>                         pm_runtime_no_callbacks(dev);
>                         ret = devm_pm_runtime_set_active_enabled(dev);
>                         if (ret < 0)
> -                               return ret;
> +                               goto err_pwrctrl_destroy;
>                 }
>
>                 if (imx_check_flag(imx_pcie, IMX_PCIE_FLAG_SKIP_L23_READY))
> @@ -2001,6 +2021,7 @@ static int imx_pcie_probe(struct platform_device *pdev)
>  err_pwrctrl_destroy:
>         if (ret != -EPROBE_DEFER)
>                 pci_pwrctrl_destroy_devices(dev);
> +       imx_pcie_detach_pd(imx_pcie);
>         return ret;
>  }
>
> --
> 2.43.0
>
>