On Sat, 5 Feb 2022 13:45:24 +0100
Philippe Mathieu-Daudé <f4bug@xxxxxxxxx> wrote:
> Previously CPUs were exposed in the QOM tree at a path
>
> /machine/unattached/device[nn]
>
> where the 'nn' of the first CPU is usually zero, but can
> vary depending on what devices were already created.
>
> With this change the CPUs are now at
>
> /machine/cpu[nn]
>
> where the 'nn' of the first CPU is always zero.
Could you add to commit message the reason behind the change?
> Note: This (intentionally) breaks compatibility with current
> libvirt code that looks for "/machine/unattached/device[0]"
> in the assumption it is the first CPU.
Why libvirt does this in the first place?
> Cc: libvir-list@xxxxxxxxxx
> Suggested-by: Daniel P. Berrangé <berrange@xxxxxxxxxx>
> Reviewed-by: Daniel P. Berrangé <berrange@xxxxxxxxxx>
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@xxxxxxxxx>
> ---
> hw/i386/x86.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/hw/i386/x86.c b/hw/i386/x86.c
> index b84840a1bb9..50bf249c700 100644
> --- a/hw/i386/x86.c
> +++ b/hw/i386/x86.c
> @@ -108,6 +108,7 @@ void x86_cpu_new(X86MachineState *x86ms, int64_t apic_id, Error **errp)
> {
> Object *cpu = object_new(MACHINE(x86ms)->cpu_type);
>
> + object_property_add_child(OBJECT(x86ms), "cpu[*]", OBJECT(cpu));
that will take in account only initial cpus, -device/device_add cpus
will still go to wherever device_add attaches them (see qdev_set_id)
> if (!object_property_set_uint(cpu, "apic-id", apic_id, errp)) {
> goto out;
> }
