Re: [PATCH v2 2/2] PCI: qcom: Implement shutdown() callback

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [High] The qcom_pcie_shutdown() callback unconditionally dereferences the `pcie` pointer, which will cause a kernel panic for firmware-managed devices.
- [Medium] Calling asynchronous pm_runtime_put() immediately before pm_runtime_disable() risks cancelling pending suspend operations and violates Power Management guidelines.
--

--- Patch [2]: [PATCH v2 2/2] PCI: qcom: Implement shutdown() callback ---
commit 321e5283c22739b1af3a513ad41fac675e68553f
Author: Manivannan Sadhasivam <[email protected]>

PCI: qcom: Implement shutdown() callback

This commit implements a shutdown callback for the Qualcomm PCIe controller.
It reuses dw_pcie_suspend_noirq() to safely bring down the link and transition
to D3cold during system shutdown or reboot.

> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index d8eb52857f69c..f6a0cbb6a49e8 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -2156,6 +2156,15 @@ static int qcom_pcie_probe(struct platform_device *pdev)
>  	return ret;
>  }
>  
> +static void qcom_pcie_shutdown(struct platform_device *pdev)
> +{
> +	struct qcom_pcie *pcie = platform_get_drvdata(pdev);
> +
> +	dw_pcie_suspend_noirq(pcie->pci);

[Severity: High]
Can pcie be NULL here? In qcom_pcie_probe(), if the device is
firmware_managed, the probe returns 0 early without allocating the pcie
structure or calling platform_set_drvdata(). Will this result in a NULL
pointer dereference during shutdown on those platforms?

> +	pm_runtime_put(&pdev->dev);
> +	pm_runtime_disable(&pdev->dev);

[Severity: Medium]
Does using the asynchronous pm_runtime_put() here risk cancelling the pending
suspend operation when pm_runtime_disable() is immediately called? Should this
use pm_runtime_put_sync() instead to ensure the suspend completes before
runtime PM is disabled?

> +}
>

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Sashiko AI review · https://sashiko.dev/#/patchset/[email protected]?part=2