Re: [PATCH v14 30/34] PCI/AER: Dequeue forwarded CXL error

[Jonathan Cameron <jonathan.cameron@huawei.com>]

On Wed, 14 Jan 2026 12:20:51 -0600
Terry Bowman <terry.bowman@amd.com> wrote:

> The AER driver now forwards CXL protocol errors to the CXL driver via a
> kfifo. The CXL driver must consume these work items and initiate protocol
> error handling while ensuring the device's RAS mappings remain valid
> throughout processing.
> 
> Implement cxl_proto_err_work_fn() to dequeue work items forwarded by the
> AER service driver. Lock the parent CXL Port device to ensure the CXL
> device's RAS registers are accessible during handling. Add pdev reference-put
> to match reference-get in AER driver. This will ensure pdev access after
> kfifo dequeue. These changes apply to CXL Ports and CXL Endpoints.
> 
> Signed-off-by: Terry Bowman <terry.bowman@amd.com>

Few things inline.
Thanks,

Jonathan

> diff --git a/drivers/cxl/core/ras.c b/drivers/cxl/core/ras.c
> index bf82880e19b4..0c640b84ad70 100644
> --- a/drivers/cxl/core/ras.c
> +++ b/drivers/cxl/core/ras.c
> @@ -117,17 +117,6 @@ static void cxl_cper_prot_err_work_fn(struct work_struct *work)

> +/*
> + * Return 'struct cxl_port *' parent CXL Port of dev
> + *
> + * Reference count increments returned port on success
> + *
> + * @pdev: Find the parent CXL Port of this device

This is a non standard type of a comment. I'd make it formal
kernel-doc.



> +
> +static void cxl_proto_err_work_fn(struct work_struct *work)
> +{
> +	struct cxl_proto_err_work_data wd;
> +
> +	while (cxl_proto_err_kfifo_get(&wd)) {

I'm probably being slow today but where does that helper come from?

> +		struct pci_dev *pdev __free(pci_dev_put) = wd.pdev;
> +
> +		if (!pdev) {
> +			pr_err_ratelimited("NULL PCI device passed in AER-CXL KFIFO\n");
> +			continue;
> +		}
> +
> +		struct cxl_port *port __free(put_cxl_port) = get_cxl_port(pdev);
> +		if (!port) {
> +			pr_err_ratelimited("Failed to find parent Port device in CXL topology.\n");
> +			continue;
> +		}
> +		guard(device)(&port->dev);
> +
> +		cxl_handle_proto_error(&wd);
> +	}
> +}