Re: [PATCH v3 2/2] PCI: qcom: Implement shutdown() callback

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] Reusing a `_noirq` suspend callback in the shutdown path without disabling interrupts creates a race condition that can cause a fatal synchronous external abort.
--

--- Patch [2]: [PATCH v3 2/2] PCI: qcom: Implement shutdown() callback ---
commit fddc2f7864ce1c4c291d73453690c4721638afe0
Author: Manivannan Sadhasivam <mani@kernel.org>

PCI: qcom: Implement shutdown() callback

This commit introduces a shutdown callback for the Qualcomm PCIe
controller. It reuses dw_pcie_suspend_noirq() to cleanly bring down
the PCIe link before system power and clocks are cut during shutdown
or reboot.

> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index d8eb52857f69c..a4284c64de276 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
[ ... ]
> @@ -2156,6 +2156,17 @@ 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);
> +
> +	if (pcie)
> +		dw_pcie_suspend_noirq(pcie->pci);

[Severity: High]
Does reusing dw_pcie_suspend_noirq() here without disabling device interrupts
create a race condition that can cause a fatal synchronous external abort?

The device_shutdown() phase runs with interrupts enabled. The suspend_noirq
hardware teardown sequence eventually disables the PCIe clocks and PHY. 

If a PCIe MSI or spurious interrupt fires after the clocks are disabled but
before the system finishes rebooting, the chained IRQ handler might attempt
to read powered-off hardware registers, resulting in a fatal bus fault.

> +
> +	pm_runtime_put_sync(&pdev->dev);
> +	pm_runtime_disable(&pdev->dev);
> +}

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260824-shutdown-v3-0-81c14bb7a1af@oss.qualcomm.com?part=2