Re: [PATCH 02/10] hw/riscv/virt: Add a switch to enable/disable ACPI

[Andrea Bolognani]

On Tue, Feb 07, 2023 at 08:20:31PM +0100, Andrew Jones wrote:
> On Tue, Feb 07, 2023 at 06:38:15AM -0800, Andrea Bolognani wrote:
> > Well, it looks like -no-acpi will come for free after all, thanks to
> > the code you pasted above, as long as the machine property follows
> > the convention established by x86, arm and (I just noticed this one)
> > loongarch.
>
> Not quite, because we also have
>
> $ grep -A1 '"no-acpi"' qemu-options.hx
> DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
>            "-no-acpi        disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM)
>
> So that means neither riscv nor loongarch get -no-acpi just by adding
> the "acpi" machine property.
>
> If the plan is to deprecate -no-acpi, then riscv can be like loongarch
> and only have the "acpi" property from the start.

Makes sense.


For the libvirt integration, do I understand correctly that the
machine property was added by commit

  commit 17e89077b7e3bc1d96540e21ddc7451c3e077049
  Author: Gerd Hoffmann <kraxel@redhat.com>
  Date:   Fri Mar 20 11:01:36 2020 +0100

    acpi: add acpi=OnOffAuto machine property to x86 and arm virt

    Remove the global acpi_enabled bool and replace it with an
    acpi OnOffAuto machine property.

    qemu throws an error now if you use -no-acpi while the machine
    type you are using doesn't support acpi in the first place.

    Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
    Message-Id: <20200320100136.11717-1-kraxel@redhat.com>
    Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
    Acked-by: Paolo Bonzini <pbonzini@redhat.com>
    Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
    Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

included in QEMU 5.0? libvirt still officially supports QEMU 4.2, so
we'll have to make the use of the machine property conditional.

-- 
Andrea Bolognani / Red Hat / Virtualization