Re: [PATCH-for-10.0 v2 05/13] hw/pci: Propagate bar_at_addr_0_refused to pci_root_bus_internal_init()

[Peter Maydell]

On Tue, 26 Nov 2024 at 11:22, Philippe Mathieu-Daudé <philmd@linaro.org> wrote:
>
> Have pci_root_bus_internal_init() callers set the
> 'bar_at_addr_0_refused' argument. No logical change.
>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>  hw/pci/pci.c | 11 +++++++----
>  1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index 27b66583e54..8eacb8f82fc 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -529,7 +529,8 @@ static bool machine_refuses_bar_at_addr_0(void)
>
>  static void pci_root_bus_internal_init(PCIBus *bus, DeviceState *parent,
>                                         MemoryRegion *mem, MemoryRegion *io,
> -                                       uint8_t devfn_min)
> +                                       uint8_t devfn_min,
> +                                       bool bar_at_addr_0_refused)
>  {
>      assert(PCI_FUNC(devfn_min) == 0);
>      bus->devfn_min = devfn_min;
> @@ -537,7 +538,7 @@ static void pci_root_bus_internal_init(PCIBus *bus, 
> DeviceState *parent,
>      bus->address_space_mem = mem;
>      bus->address_space_io = io;
>      bus->flags |= PCI_BUS_IS_ROOT;
> -    if (machine_refuses_bar_at_addr_0()) {
> +    if (bar_at_addr_0_refused && machine_refuses_bar_at_addr_0()) {

Should this be || rather than &&  ? If I understand the
intent correctly, we want to prevent a BAR at address 0
if either:
 * the MachineClass field says we don't want one
   (legacy handling, eventually goes away)
 * the new command line argument says we don't want one

rather than only if *both* say "no address 0" ?

thanks
-- PMM