Re: [Qemu-devel] [PATCH 1/1] display/bochs: fix pcie support

[Alex Williamson]

On Mon, 12 Aug 2019 08:52:21 +0200
Gerd Hoffmann <address@hidden> wrote:

> Set QEMU_PCI_CAP_EXPRESS unconditionally in init(), then clear it in
> realize() in case the device is not connected to a PCIe bus.
> 
> This makes sure the pci config space allocation is big enough, so
> accessing the PCIe extended config space doesn't overflow the pci
> config space buffer.
> 
> Signed-off-by: Gerd Hoffmann <address@hidden>
> ---
>  hw/display/bochs-display.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)


Reviewed-by: Alex Williamson <address@hidden>

 
> diff --git a/hw/display/bochs-display.c b/hw/display/bochs-display.c
> index 582133dd719c..8e83b5164b67 100644
> --- a/hw/display/bochs-display.c
> +++ b/hw/display/bochs-display.c
> @@ -297,9 +297,10 @@ static void bochs_display_realize(PCIDevice *dev, Error 
> **errp)
>      }
>  
>      if (pci_bus_is_express(pci_get_bus(dev))) {
> -        dev->cap_present |= QEMU_PCI_CAP_EXPRESS;
>          ret = pcie_endpoint_cap_init(dev, 0x80);
>          assert(ret > 0);
> +    } else {
> +        dev->cap_present &= ~QEMU_PCI_CAP_EXPRESS;
>      }
>  
>      memory_region_set_log(&s->vram, true, DIRTY_MEMORY_VGA);
> @@ -322,11 +323,15 @@ static void bochs_display_set_big_endian_fb(Object 
> *obj, bool value,
>  
>  static void bochs_display_init(Object *obj)
>  {
> +    PCIDevice *dev = PCI_DEVICE(obj);
> +
>      /* Expose framebuffer byteorder via QOM */
>      object_property_add_bool(obj, "big-endian-framebuffer",
>                               bochs_display_get_big_endian_fb,
>                               bochs_display_set_big_endian_fb,
>                               NULL);
> +
> +    dev->cap_present |= QEMU_PCI_CAP_EXPRESS;
>  }
>  
>  static void bochs_display_exit(PCIDevice *dev)