Re: [RFC PATCH v2 07/13] hw/arm/virt-acpi-build: distinguish possible and present cpus Message

[Andrew Jones]

You need to remove 'Message' from the summary.

On Tue, Oct 20, 2020 at 09:14:34PM +0800, Ying Fang wrote:
> When building ACPI tables regarding CPUs we should always build
> them for the number of possible CPUs, not the number of present
> CPUs. We then ensure only the present CPUs are enabled.
> 
> Signed-off-by: Andrew Jones <drjones@redhat.com>

I guess my s-o-b is here because this is a rework of

https://github.com/rhdrjones/qemu/commit/b18d7a889f424b8a8679c43d7f4804fdeeeaf3fd

I think it changed enough you could just drop my authorship. A
based-on comment in the commit message would be more than enough.

Comment on the patch below.

> Signed-off-by: Ying Fang <fangying1@huawei.com>
> ---
>  hw/arm/virt-acpi-build.c | 17 ++++++++++++-----
>  1 file changed, 12 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index a222981737..fae5a26741 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -57,14 +57,18 @@
>  
>  #define ARM_SPI_BASE 32
>  
> -static void acpi_dsdt_add_cpus(Aml *scope, int cpus)
> +static void acpi_dsdt_add_cpus(Aml *scope, VirtMachineState *vms)
>  {
>      uint16_t i;
> +    CPUArchIdList *possible_cpus = MACHINE(vms)->possible_cpus;
>  
> -    for (i = 0; i < cpus; i++) {
> +    for (i = 0; i < possible_cpus->len; i++) {
>          Aml *dev = aml_device("C%.03X", i);
>          aml_append(dev, aml_name_decl("_HID", aml_string("ACPI0007")));
>          aml_append(dev, aml_name_decl("_UID", aml_int(i)));
> +        if (possible_cpus->cpus[i].cpu == NULL) {
> +            aml_append(dev, aml_name_decl("_STA", aml_int(0)));
> +        }
>          aml_append(scope, dev);
>      }
>  }
> @@ -470,6 +474,7 @@ build_madt(GArray *table_data, BIOSLinker *linker, 
> VirtMachineState *vms)
>      const int *irqmap = vms->irqmap;
>      AcpiMadtGenericDistributor *gicd;
>      AcpiMadtGenericMsiFrame *gic_msi;
> +    int possible_cpus = MACHINE(vms)->possible_cpus->len;
>      int i;
>  
>      acpi_data_push(table_data, sizeof(AcpiMultipleApicTable));
> @@ -480,7 +485,7 @@ build_madt(GArray *table_data, BIOSLinker *linker, 
> VirtMachineState *vms)
>      gicd->base_address = cpu_to_le64(memmap[VIRT_GIC_DIST].base);
>      gicd->version = vms->gic_version;
>  
> -    for (i = 0; i < MACHINE(vms)->smp.cpus; i++) {
> +    for (i = 0; i < possible_cpus; i++) {
>          AcpiMadtGenericCpuInterface *gicc = acpi_data_push(table_data,
>                                                             sizeof(*gicc));
>          ARMCPU *armcpu = ARM_CPU(qemu_get_cpu(i));
> @@ -495,7 +500,9 @@ build_madt(GArray *table_data, BIOSLinker *linker, 
> VirtMachineState *vms)
>          gicc->cpu_interface_number = cpu_to_le32(i);
>          gicc->arm_mpidr = cpu_to_le64(armcpu->mp_affinity);
>          gicc->uid = cpu_to_le32(i);
> -        gicc->flags = cpu_to_le32(ACPI_MADT_GICC_ENABLED);
> +        if (i < MACHINE(vms)->smp.cpus) {

Shouldn't this be

        if (possible_cpus->cpus[i].cpu != NULL) {

> +            gicc->flags = cpu_to_le32(ACPI_MADT_GICC_ENABLED);
> +        }
>  
>          if (arm_feature(&armcpu->env, ARM_FEATURE_PMU)) {
>              gicc->performance_interrupt = cpu_to_le32(PPI(VIRTUAL_PMU_IRQ));
> @@ -599,7 +606,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker, 
> VirtMachineState *vms)
>       * the RTC ACPI device at all when using UEFI.
>       */
>      scope = aml_scope("\\_SB");
> -    acpi_dsdt_add_cpus(scope, ms->smp.cpus);
> +    acpi_dsdt_add_cpus(scope, vms);
>      acpi_dsdt_add_uart(scope, &memmap[VIRT_UART],
>                         (irqmap[VIRT_UART] + ARM_SPI_BASE));
>      if (vmc->acpi_expose_flash) {
> -- 
> 2.23.0
> 
>

Thanks,
drew