On Fri, Sep 21, 2012 at 1:52 PM, Bjorn Helgaas <bhelgaas@google.com> wrote:
> On Wed, Sep 19, 2012 at 12:54 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>> --- a/drivers/gpu/vga/vgaarb.c
>> +++ b/drivers/gpu/vga/vgaarb.c
>> @@ -141,6 +141,12 @@ EXPORT_SYMBOL_GPL(vga_default_device);
>>
>>  void vga_set_default_device(struct pci_dev *pdev)
>>  {
>> +       if (vga_default)
>> +               pci_dev_put(vga_default);
>> +
>> +       if (pdev)
>> +               pdev = pci_dev_get(pdev);
>> +
>>         vga_default = pdev;
>
> I think this is equivalent to:
>
>     pci_dev_put(vga_default);
>     vga_default = pci_dev_get(pdev);

ah, i missed that, pci_dev_put and pci_dev_get check that inside.

>
> I haven't seen an answer to Matthew's question about whether we want
> to check for "vga_default == pdev".

yes, that could avoid the extra put/get pair.

Please check updated version.

-Yinghai
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