PCI Express does not allow hot-plug on pcie.0. Check for Q35 in
acpi_pcihp_disable_root_bus() to be able to forbid hot-plug using the
'acpi-root-pci-hotplug' flag.

Signed-off-by: Julia Suvorova <jusual@redhat.com>
---
 hw/acpi/pcihp.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
index 39b1f74442..ff23104aea 100644
--- a/hw/acpi/pcihp.c
+++ b/hw/acpi/pcihp.c
@@ -107,13 +107,14 @@ static void acpi_set_pci_info(void)
 static void acpi_pcihp_disable_root_bus(void)
 {
     static bool root_hp_disabled;
+    Object *host = acpi_get_i386_pci_host();
     PCIBus *bus;
 
     if (root_hp_disabled) {
         return;
     }
 
-    bus = find_i440fx();
+    bus = PCI_HOST_BRIDGE(host)->bus;
     if (bus) {
         /* setting the hotplug handler to NULL makes the bus non-hotpluggable */
         qbus_set_hotplug_handler(BUS(bus), NULL);
-- 
2.25.4

On Thu, 24 Sep 2020 09:00:07 +0200
Julia Suvorova <jusual@redhat.com> wrote:

> PCI Express does not allow hot-plug on pcie.0. Check for Q35 in
> acpi_pcihp_disable_root_bus() to be able to forbid hot-plug using the
> 'acpi-root-pci-hotplug' flag.
> 
> Signed-off-by: Julia Suvorova <jusual@redhat.com>

Reviewed-by: Igor Mammedov <imammedo@redhat.com>

> ---
>  hw/acpi/pcihp.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
> index 39b1f74442..ff23104aea 100644
> --- a/hw/acpi/pcihp.c
> +++ b/hw/acpi/pcihp.c
> @@ -107,13 +107,14 @@ static void acpi_set_pci_info(void)
>  static void acpi_pcihp_disable_root_bus(void)
>  {
>      static bool root_hp_disabled;
> +    Object *host = acpi_get_i386_pci_host();
>      PCIBus *bus;
>  
>      if (root_hp_disabled) {
>          return;
>      }
>  
> -    bus = find_i440fx();
> +    bus = PCI_HOST_BRIDGE(host)->bus;
>      if (bus) {
>          /* setting the hotplug handler to NULL makes the bus non-hotpluggable */
>          qbus_set_hotplug_handler(BUS(bus), NULL);

On Thu, Sep 24, 2020 at 12:30 PM Julia Suvorova <jusual@redhat.com> wrote:
>
> PCI Express does not allow hot-plug on pcie.0. Check for Q35 in
> acpi_pcihp_disable_root_bus() to be able to forbid hot-plug using the
> 'acpi-root-pci-hotplug' flag.

I think what this change is doing here is making
acpi_pcihp_disable_root_bus() function compatible with q35 as well.

>
> Signed-off-by: Julia Suvorova <jusual@redhat.com>
> ---
>  hw/acpi/pcihp.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
> index 39b1f74442..ff23104aea 100644
> --- a/hw/acpi/pcihp.c
> +++ b/hw/acpi/pcihp.c
> @@ -107,13 +107,14 @@ static void acpi_set_pci_info(void)
>  static void acpi_pcihp_disable_root_bus(void)
>  {
>      static bool root_hp_disabled;
> +    Object *host = acpi_get_i386_pci_host();
>      PCIBus *bus;
>
>      if (root_hp_disabled) {
>          return;
>      }
>
> -    bus = find_i440fx();
> +    bus = PCI_HOST_BRIDGE(host)->bus;
>      if (bus) {
>          /* setting the hotplug handler to NULL makes the bus non-hotpluggable */
>          qbus_set_hotplug_handler(BUS(bus), NULL);
> --
> 2.25.4
>