Re: [Qemu-devel] [PATCH] pci: allow 32-bit PCI IO accesses to pass through the PCI bridge

[Laszlo Ersek]

On 09/22/17 14:18, Mark Cave-Ayland wrote:
> Whilst the underlying PCI bridge implementation supports 32-bit PCI IO
> accesses, unfortunately they are truncated at the legacy 64K limit.
> 
> Signed-off-by: Mark Cave-Ayland <address@hidden>
> ---
>  hw/pci/pci_bridge.c |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/pci/pci_bridge.c b/hw/pci/pci_bridge.c
> index 17feae5..a47d257 100644
> --- a/hw/pci/pci_bridge.c
> +++ b/hw/pci/pci_bridge.c
> @@ -379,7 +379,8 @@ void pci_bridge_initfn(PCIDevice *dev, const char 
> *typename)
>      sec_bus->address_space_mem = &br->address_space_mem;
>      memory_region_init(&br->address_space_mem, OBJECT(br), "pci_bridge_pci", 
> UINT64_MAX);
>      sec_bus->address_space_io = &br->address_space_io;
> -    memory_region_init(&br->address_space_io, OBJECT(br), "pci_bridge_io", 
> 65536);
> +    memory_region_init(&br->address_space_io, OBJECT(br), "pci_bridge_io",
> +                       UINT32_MAX);
>      br->windows = pci_bridge_region_init(br);
>      QLIST_INIT(&sec_bus->child);
>      QLIST_INSERT_HEAD(&parent->child, sec_bus, sibling);
> 

Based on the commit message, I assume this change is guest-visible. If
so, should it be made dependent on a compat property, so that it doesn't
cause problems with migration?

Thanks,
Laszlo