Re: [PATCH v3] PCI: imx6: fix resource leaks in probe error paths

On Mon, Aug 24, 2026 at 03:55:12PM +0800, hanzhijian wrote:

Don't post new version patch at old thread.

>
> 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 creates device links to them, but the device links are only kept
>   in a local variable and nothing detaches the domains on probe failure
>   or deferral, so all of them 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
>   and device links that were already attached.
>
> Save the device links, add imx_pcie_detach_pd() to release the power
> domains and device links in reverse order of acquisition, call it from
> the probe error paths, and make imx_pcie_attach_pd() release everything
> it has attached so far on failure.
>
> Reported-by: [email protected]
> Link: https://lore.kernel.org/all/[email protected]/
> Signed-off-by: hanzhijian <[email protected]>
> ---
>  drivers/pci/controller/dwc/pci-imx6.c | 42 ++++++++++++++++++++++++---
>  1 file changed, 38 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 39790e66b..467006d83 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -182,6 +182,9 @@ struct imx_pcie {
>         struct device           *pd_pcie;
>         /* power domain for pcie phy */
>         struct device           *pd_pcie_phy;
> +       /* device links for the power domains */
> +       struct device_link      *pd_link;
> +       struct device_link      *pd_phy_link;
>         struct phy              *phy;
>         const struct imx_pcie_drvdata *drvdata;
>
> @@ -639,6 +642,26 @@ static int imx6q_pcie_abort_handler(unsigned long addr,
>  }
>  #endif
>
> +static void imx_pcie_detach_pd(struct imx_pcie *imx_pcie)
> +{
> +       if (imx_pcie->pd_phy_link) {
> +               device_link_del(imx_pcie->pd_phy_link);
> +               imx_pcie->pd_phy_link = NULL;
> +       }
> +       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 (imx_pcie->pd_link) {
> +               device_link_del(imx_pcie->pd_link);
> +               imx_pcie->pd_link = 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);
> @@ -660,12 +683,18 @@ static int imx_pcie_attach_pd(struct device *dev)
>                         DL_FLAG_RPM_ACTIVE);
>         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_link = link;
>
>         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 |

Does DL_FLAG_AUTOREMOVE_CONSUMER work?

Frank

> @@ -673,8 +702,10 @@ static int imx_pcie_attach_pd(struct device *dev)
>                         DL_FLAG_RPM_ACTIVE);
>         if (!link) {
>                 dev_err(dev, "Failed to add device_link to pcie_phy pd\n");
> +               imx_pcie_detach_pd(imx_pcie);
>                 return -EINVAL;
>         }
> +       imx_pcie->pd_phy_link = link;
>
>         return 0;
>  }
> @@ -1956,8 +1987,10 @@ 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);
>                 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 +2008,7 @@ 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 +2034,7 @@ 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
>
>