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

[Andrea Bolognani]

On Tue, Feb 07, 2023 at 03:02:19PM +0100, Thomas Huth wrote:
> On 07/02/2023 14.56, Andrea Bolognani wrote:
> > It looks like i440fx and q35 both have an 'acpi' machine property. Is
> > -no-acpi just sugar for acpi=off?
>
> Yes, it is, see softmmu/vl.c:
>
>             case QEMU_OPTION_no_acpi:
>                 qdict_put_str(machine_opts_dict, "acpi", "off");
>                 break;
>
> > Is it considered desirable to get rid of -no-acpi?
>
> Sounds like a good idea, indeed!
>
> > If so, we should follow the usual deprecation
> > process and get rid of it after libvirt has had a chance to adapt.
> >
> > In the scenario described above, it would make sense for RISC-V to
> > only offer the machine type option (assuming that -no-acpi doesn't
> > come for free with that) instead of putting additional effort into
> > implementing an interface that is already on its way out.
>
> I agree. IMHO the machine parameter should be enough, no need to introduce
> "-no-acpi" here.

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.

So I guess the -no-acpi deprecation can be handled separately, and
the only thing that needs changing in the current patch is making
sure that ACPI is opt-out rather than opt-in, as is the case for
other architectures :)

-- 
Andrea Bolognani / Red Hat / Virtualization