Re: [RFC PATCH 09/15] meson.build: introduce CONFIG_XEN_HVM flag

[Philippe Mathieu-Daudé]

On 11/5/20 6:51 PM, Alex Bennée wrote:
> While Xen traditionally uses i386-softmmu to run it's PV models on all
> architectures some models are very much x86 only. This includes the
> full hardware virtualisation (HVM) which is only used on x86 HW. By
> introducing the symbol we can also fix the inclusion of
> XEN_PCI_PASSTHROUGH which should only be built for x86 (and Linux)
> systems.
> 
> Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
> ---
>  meson.build   | 6 +++++-
>  accel/Kconfig | 3 +++
>  2 files changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/meson.build b/meson.build
> index 58e95227ea..46e4c2fc3a 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -83,6 +83,7 @@ endif
>  if cpu in ['x86', 'x86_64']
>    accelerator_targets += {
>      'CONFIG_HAX': ['i386-softmmu', 'x86_64-softmmu'],
> +    'CONFIG_XEN_HVM': ['i386-softmmu', 'x86_64-softmmu'],

I'm confused while looking at
https://wiki.xen.org/wiki/Xen_Project_Software_Overview#ARM_Hosts

Maybe it makes sense to add both CONFIG_XEN_PV /
CONFIG_XEN_HVM accelerators?

>      'CONFIG_HVF': ['x86_64-softmmu'],
>      'CONFIG_WHPX': ['i386-softmmu', 'x86_64-softmmu'],
>    }
> @@ -204,6 +205,9 @@ if not get_option('kvm').disabled() and targetos == 
> 'linux'
>  endif
>  if not get_option('xen').disabled() and 'CONFIG_XEN_BACKEND' in config_host
>    accelerators += 'CONFIG_XEN'
> +  if host_machine.cpu() == 'x86_64'

Are you sure it is restricted to 64-bit host? I can't find
the reference.

> +    accelerators += 'CONFIG_XEN_HVM'
> +  endif
>    have_xen_pci_passthrough = not 
> get_option('xen_pci_passthrough').disabled() and targetos == 'linux'