Re: [PATCH] PCI: qcom: Ignore -ENODEV after Root Port reset

[Niklas Cassel]

Hello Konrad,

On Wed, Sep 16, 2026 at 02:37:49PM +0200, Konrad Dybcio wrote:
> Root Port recovery may race with a device hot-unplug. In that case,
> dw_pcie_wait_for_link() returns -ENODEV because no device is detected
> after the controller has been successfully reset.
> 
> This is a valid outcome and should not cause Root Port recovery to
> fail. Ignore -ENODEV while continuing to propagate other link-training
> errors.
> 
> Assisted-by: LLM
> Fixes: 4d88cb82a6d9 ("PCI: qcom: Implement .reset_root_port() and use for link down")
> Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>
> ---
>  drivers/pci/controller/dwc/pcie-qcom.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index ee63a6ec99de4d07c16b8d6cb68df0d92f822cd8..3d3be9bf798b7c247d69969d6570385b8648123f 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -1880,6 +1880,9 @@ static int qcom_pcie_reset_root_port(struct pci_host_bridge *bridge,
>  	qcom_pcie_start_link(pci);
>  
>  	ret = dw_pcie_wait_for_link(pci);
> +	/* This linkdown might have been a hot-unplug */
> +	if (ret == -ENODEV)
> +		ret = 0;
>  	if (ret)
>  		return ret;


I did not know that pcie-qcom supported hotplug.

Last when I was discussing this with Mani, I'm quite sure that he said that
it doesn't, see:
https://lore.kernel.org/all/20251222064207.3246632-8-cassel@xxxxxxxxxx/

If that is the case, perhaps the commit message and code comment should be
clarified, so it is more clear what it actually means.


Kind regards,
Niklas