Re: [PATCH] xen/pci: Try harder to get PXM information for Xen

[Ross Lagerwall <ross.lagerwall@citrix.com>]

On 08/04/15 18:17, Boris Ostrovsky wrote:
> On 04/08/2015 12:44 PM, David Vrabel wrote:
>> On 08/04/15 15:01, Boris Ostrovsky wrote:
>>> On 04/08/2015 09:39 AM, Ross Lagerwall wrote:
>>>> If the device being added to Xen is not contained in the ACPI table,
>>>> walk the PCI device tree to find a parent that is contained in the ACPI
>>>> table before finding the PXM information from this device.
>>>>
>>>> Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
>>>> ---
>>>>    drivers/xen/pci.c | 15 +++++++++++++--
>>>>    1 file changed, 13 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/drivers/xen/pci.c b/drivers/xen/pci.c
>>>> index 95ee430..6837181 100644
>>>> --- a/drivers/xen/pci.c
>>>> +++ b/drivers/xen/pci.c
>>>> @@ -19,6 +19,7 @@
>>>>      #include <linux/pci.h>
>>>>    #include <linux/acpi.h>
>>>> +#include <linux/pci-acpi.h>
>>>>    #include <xen/xen.h>
>>>>    #include <xen/interface/physdev.h>
>>>>    #include <xen/interface/xen.h>
>>>> @@ -67,8 +68,18 @@ static int xen_add_device(struct device *dev)
>>>>      #ifdef CONFIG_ACPI
>>>>            handle = ACPI_HANDLE(&pci_dev->dev);
>>>> -        if (!handle && pci_dev->bus->bridge)
>>>> -            handle = ACPI_HANDLE(pci_dev->bus->bridge);
>>>> +        if (!handle) {
>>>> +            /*
>>>> +             * This device was not listed in the ACPI name space at
>>>> +             * all. Try to get acpi handle of parent pci bus.
>>>> +             */
>>>> +            struct pci_bus *pbus;
>>>> +            for (pbus = pci_dev->bus; pbus; pbus = pbus->parent) {
>>>> +                handle = acpi_pci_get_bridge_handle(pbus);
>>>> +                if (handle)
>>>> +                    break;
>>>> +            }
>>>> +        }
>>>>    #ifdef CONFIG_PCI_IOV
>>>>            if (!handle && pci_dev->is_virtfn)
>>>>                handle = ACPI_HANDLE(physfn->bus->bridge);
>>>
>>> Shouldn't we first look at physfn, before going up the tree?
>> That sounds sensible but should be a separate pre-requisite patch.
>
> It's already there: the last two (unchanged) lines above. The added
> chunk should just move to after those two.
>

OK, I can swap it around.

-- 
Ross Lagerwall