Re: [PATCH] pci: of : fix BUG: unable to handle kernel

[Rob Herring <robherring2@gmail.com>]

On Tue, Mar 10, 2015 at 10:25 AM, Murali Karicheri <m-karicheri2@ti.com> wrote:
> On some platforms such as that based on x86, ia64 etc, root bus is
> created with parent node passed in as NULL to pci_create_root_bus().
> On these platforms, the patch series "PCI: get DMA configuration from
> parent device" when applied causes kernel crash. So add a check for this
> in of_pci_dma_configure()

Wouldn't these arches have OF disabled and call an empty function?
Regardless, we still need this.

> Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>

I'm assuming Bjorn will apply this.

Acked-by: Rob Herring <robh@kernel.org>

> ---
>  drivers/of/of_pci.c |    4 ++++
>  1 file changed, 4 insertions(+)
>
> diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
> index 86d3c38..a8e485c 100644
> --- a/drivers/of/of_pci.c
> +++ b/drivers/of/of_pci.c
> @@ -129,6 +129,10 @@ void of_pci_dma_configure(struct pci_dev *pci_dev)
>         struct device *dev = &pci_dev->dev;
>         struct device *bridge = pci_get_host_bridge_device(pci_dev);
>
> +       /* Some platforms can have bridge->parent set to NULL */
> +       if (!bridge->parent)
> +               return;
> +
>         of_dma_configure(dev, bridge->parent->of_node);
>         pci_put_host_bridge_device(bridge);
>  }
> --
> 1.7.9.5
>