Re: [Qemu-devel] [PATCH V2] acpi-build: Set FORCE_APIC_CLUSTER_MODEL bit for FADT flags

[zhanghailiang]

Hi,

Ping...

Thanks,
zhanghailiang

On 2014/8/29 11:52, zhanghailiang wrote:
> If we start Windows 2008 R2 DataCenter with number of cpu less than 8,
> The system will use APIC Flat Logical destination mode as default configuration,
> Which has an upper limit of 8 CPUs.
>
> The fault is that VM can not show all processors within Task Manager if
> we hot-add cpus when the number of cpus in VM extends the limit of 8.
>
> If we use cluster destination model, the problem will be solved.
>
> Signed-off-by: huangzhichao<address@hidden>
> Signed-off-by: zhanghailiang<address@hidden>
> ---
> v2:
>   - Set this bit when max_cpus>  8
> ---
>   hw/i386/acpi-build.c | 6 ++++++
>   1 file changed, 6 insertions(+)
>
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index 85e5834..cdc3b08 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -550,6 +550,12 @@ static void fadt_setup(AcpiFadtDescriptorRev1 *fadt, 
> AcpiPmInfo *pm)
>                                 (1<<  ACPI_FADT_F_SLP_BUTTON) |
>                                 (1<<  ACPI_FADT_F_RTC_S4));
>       fadt->flags |= cpu_to_le32(1<<  ACPI_FADT_F_USE_PLATFORM_CLOCK);
> +    /* APIC destination mode ("Flat Logical") has an upper limit of 8 CPUs
> +     * For more than 8 CPUs, "Clustered Logical" mode has to be used
> +     */
> +    if (max_cpus>  8) {
> +        fadt->flags |= cpu_to_le32(1<<  ACPI_FADT_F_FORCE_APIC_CLUSTER_MODEL);
> +    }
>   }