Re: [PULL v3 11/27] multi-process: setup PCI host bridge for remote device

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 2/5/21 5:44 PM, Stefan Hajnoczi wrote:
> From: Jagannathan Raman <jag.raman@oracle.com>
> 
> PCI host bridge is setup for the remote device process. It is
> implemented using remote-pcihost object. It is an extension of the PCI
> host bridge setup by QEMU.
> Remote-pcihost configures a PCI bus which could be used by the remote
> PCI device to latch on to.
> 
> Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
> Signed-off-by: John G Johnson <john.g.johnson@oracle.com>
> Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
> Message-id: 0871ba857abb2eafacde07e7fe66a3f12415bfb2.1611938319.git.jag.raman@oracle.com
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
>  MAINTAINERS                  |  2 +
>  include/hw/pci-host/remote.h | 29 ++++++++++++++
>  hw/pci-host/remote.c         | 75 ++++++++++++++++++++++++++++++++++++
>  hw/pci-host/Kconfig          |  3 ++
>  hw/pci-host/meson.build      |  1 +
>  hw/remote/Kconfig            |  1 +
>  6 files changed, 111 insertions(+)
>  create mode 100644 include/hw/pci-host/remote.h
>  create mode 100644 hw/pci-host/remote.c
...

> +static const TypeInfo remote_pcihost_info = {
> +    .name = TYPE_REMOTE_PCIHOST,
> +    .parent = TYPE_PCIE_HOST_BRIDGE,

                 ^^^^^^^^^^^^^^^^^^^^^

> +    .instance_size = sizeof(RemotePCIHost),
> +    .class_init = remote_pcihost_class_init,
> +};
> +
> +static void remote_pcihost_register(void)
> +{
> +    type_register_static(&remote_pcihost_info);
> +}
> +
> +type_init(remote_pcihost_register)
> diff --git a/hw/pci-host/Kconfig b/hw/pci-host/Kconfig
> index eb03f0489d..8b8c763c28 100644
> --- a/hw/pci-host/Kconfig
> +++ b/hw/pci-host/Kconfig
> @@ -65,3 +65,6 @@ config PCI_POWERNV
>      select PCI_EXPRESS
>      select MSI_NONBROKEN
>      select PCIE_PORT
> +
> +config REMOTE_PCIHOST
> +    bool

       select CONFIG_PCI_EXPRESS ?

(Reported by Peter Maydell on s390x)

Side question, does it make sense to enable this feature by
default on all architectures?

Regards,

Phil.