[Qemu-devel] Re: [PATCH 2/4] pci init: fail qemu if devfn exceeding the max function number supported on bus

[Michael S. Tsirkin]

On Tue, Aug 24, 2010 at 09:27:10PM +0800, Ken CC wrote:
> Check if devfn < PCIBUS_MAX_DEVICES * PCI_FUNCTIONS_PER_DEVICE
> 
> Signed-off-by: Ken CC <address@hidden>
> ---
>  hw/pci.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/hw/pci.c b/hw/pci.c
> index 9234fe3..fc4becd 100644
> --- a/hw/pci.c
> +++ b/hw/pci.c
> @@ -747,6 +747,7 @@ static PCIDevice *do_pci_register_device(PCIDevice 
> *pci_dev, PCIBus *bus,
>                                           PCIConfigWriteFunc *config_write,
>                                           bool is_bridge)
>  {
> +    assert(devfn / PCI_FUNCTIONS_PER_DEVICE < PCIBUS_MAX_DEVICES);

I guess it'll happen to work even for < 0, but it might be obvious
to only do this in >= 0 case.
Just remove the 'else' and stick the assert there.


>      if (devfn < 0) {
>          for(devfn = bus->devfn_min ; devfn < ARRAY_SIZE(bus->devices);
>              devfn += PCI_FUNC_MAX) {