Re: [PATCH v5 13/16] cxl/pci: Add error handler for CXL PCIe Port RAS errors

Gregory Price
2025-02-07T08:01:32Z

On Tue, Jan 07, 2025 at 08:38:49AM -0600, Terry Bowman wrote:
> +static void __iomem *cxl_pci_port_ras(struct pci_dev *pdev)
> +{
> + struct cxl_port *port;
> +
> + if (!pdev)
> + return NULL;
> +
> + if ((pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT) ||
> + (pci_pcie_type(pdev) == PCI_EXP_TYPE_DOWNSTREAM)) {
> + struct cxl_dport *dport;
> + void __iomem *ras_base;
> +
> + port = find_cxl_port(&pdev->dev, &dport);
> + ras_base = dport ? dport->regs.ras : NULL;

I'm fairly certain dport can come back here uninitialized, you
probably want to put this inside the `if (port)` block and
pre-initialize dport to NULL.

> + if (port)
> + put_device(&port->dev);
> + return ras_base;

You can probably even simplify this down to something like

struct_cxl_dport *dport = NULL;

port = find_cxl_port(&pdev->dev, &dport);
if (port)
put_device(&port->dev);

return dport ? dport->regs.ras : NULL;

~Gregory