Re: [PATCH v2] hw/pci/pci: Fix slot check for plugged devices

[Stefano Garzarella]

On Tue, Oct 06, 2020 at 02:59:08PM +0200, Julia Suvorova wrote:
> If devfn is assigned automatically, 'else' clauses will never be
> executed. And if it does not matter for the reserved and available
> devfn, because we have already checked it, the check for function0
> needs to be done again.
> 
> Steps to reproduce:
> 1. Run QEMU with:
>         -M q35 \
>         -device pcie-root-port,id=rp,.. \
>         -device pci-device,bus=rp
> 2. Add a new device to the same port:
>         device_add pci-device,bus=rp
> 
> The last command will add the device to slot 1 instead of
> failing with "PCI: slot 0 function 0 already occupied..."
> 
> Signed-off-by: Julia Suvorova <jusual@redhat.com>
> ---
> v2:
>     * add example to the commit message [Michael]
> 
>  hw/pci/pci.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index de0fae10ab..ae132b0b52 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -1034,8 +1034,9 @@ static PCIDevice *do_pci_register_device(PCIDevice 
> *pci_dev,
>                     PCI_SLOT(devfn), PCI_FUNC(devfn), name,
>                     bus->devices[devfn]->name);
>          return NULL;
> -    } else if (dev->hotplugged &&
> -               pci_get_function_0(pci_dev)) {
> +    };
        ^
This semicolon seems unnecessary, can we take it out?

Thanks,
Stefano

> +
> +    if (dev->hotplugged && pci_get_function_0(pci_dev)) {
>          error_setg(errp, "PCI: slot %d function 0 already ocuppied by %s,"
>                     " new func %s cannot be exposed to guest.",
>                     PCI_SLOT(pci_get_function_0(pci_dev)->devfn),
> -- 
> 2.25.4
> 
>