Re: [PATCH v6 1/2] hw/i386/pc: Default to use SMBIOS 3.0 for newer machine models

[Michael S. Tsirkin]

On Wed, Jun 07, 2023 at 03:57:16PM -0500, Suravee Suthikulpanit wrote:
> Currently, pc-q35 and pc-i44fx machine models are default to use SMBIOS 2.8
> (32-bit entry point). Since SMBIOS 3.0 (64-bit entry point) is now fully
> supported since QEMU 7.0, default to use SMBIOS 3.0 for newer machine
> models. This is necessary to avoid the following message when launching
> a VM with large number of vcpus.
> 
>    "SMBIOS 2.1 table length 66822 exceeds 65535"
> 
> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>

For some reason this causes a diff in ACPI:

$ diff -u /tmp/asl-WQRZ61.dsl /tmp/asl-S25X61.dsl 
--- /tmp/asl-WQRZ61.dsl 2023-06-23 05:37:54.067525946 -0400
+++ /tmp/asl-S25X61.dsl 2023-06-23 05:37:54.073525987 -0400
@@ -5,13 +5,13 @@
  * 
  * Disassembling to symbolic ASL+ operators
  *
- * Disassembly of /tmp/aml-IROZ61, Fri Jun 23 05:37:54 2023
+ * Disassembly of tests/data/acpi/q35/SSDT.dimmpxm, Fri Jun 23 05:37:54 2023
  *
  * Original Table Header:
  *     Signature        "SSDT"
  *     Length           0x00000717 (1815)
  *     Revision         0x01
- *     Checksum         0xBC
+ *     Checksum         0xAC
  *     OEM ID           "BOCHS "
  *     OEM Table ID     "NVDIMM"
  *     OEM Revision     0x00000001 (1)
@@ -389,6 +389,6 @@
         }
     }
 
-    Name (MEMA, 0x07FFE000)
+    Name (MEMA, 0x07FFF000)
 }
 

Igor, any idea why?



> ---
>  hw/i386/pc.c         | 4 +++-
>  hw/i386/pc_piix.c    | 5 +++++
>  hw/i386/pc_q35.c     | 5 +++++
>  include/hw/i386/pc.h | 1 +
>  4 files changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index bb62c994fa..33ffb03a32 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -1853,6 +1853,7 @@ static void pc_machine_set_max_fw_size(Object *obj, 
> Visitor *v,
>  static void pc_machine_initfn(Object *obj)
>  {
>      PCMachineState *pcms = PC_MACHINE(obj);
> +    PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
>  
>  #ifdef CONFIG_VMPORT
>      pcms->vmport = ON_OFF_AUTO_AUTO;
> @@ -1860,7 +1861,7 @@ static void pc_machine_initfn(Object *obj)
>      pcms->vmport = ON_OFF_AUTO_OFF;
>  #endif /* CONFIG_VMPORT */
>      pcms->max_ram_below_4g = 0; /* use default */
> -    pcms->smbios_entry_point_type = SMBIOS_ENTRY_POINT_TYPE_32;
> +    pcms->smbios_entry_point_type = pcmc->default_smbios_ep_type;
>  
>      /* acpi build is enabled by default if machine supports it */
>      pcms->acpi_build_enabled = PC_MACHINE_GET_CLASS(pcms)->has_acpi_build;
> @@ -1980,6 +1981,7 @@ static void pc_machine_class_init(ObjectClass *oc, void 
> *data)
>      mc->nvdimm_supported = true;
>      mc->smp_props.dies_supported = true;
>      mc->default_ram_id = "pc.ram";
> +    pcmc->default_smbios_ep_type = SMBIOS_ENTRY_POINT_TYPE_64;
>  
>      object_class_property_add(oc, PC_MACHINE_MAX_RAM_BELOW_4G, "size",
>          pc_machine_get_max_ram_below_4g, pc_machine_set_max_ram_below_4g,
> diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
> index d5b0dcd1fe..49462b0e29 100644
> --- a/hw/i386/pc_piix.c
> +++ b/hw/i386/pc_piix.c
> @@ -476,11 +476,16 @@ DEFINE_I440FX_MACHINE(v8_1, "pc-i440fx-8.1", NULL,
>  
>  static void pc_i440fx_8_0_machine_options(MachineClass *m)
>  {
> +    PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
> +
>      pc_i440fx_8_1_machine_options(m);
>      m->alias = NULL;
>      m->is_default = false;
>      compat_props_add(m->compat_props, hw_compat_8_0, hw_compat_8_0_len);
>      compat_props_add(m->compat_props, pc_compat_8_0, pc_compat_8_0_len);
> +
> +    /* For pc-i44fx-8.0 and older, use SMBIOS 2.8 by default */
> +    pcmc->default_smbios_ep_type = SMBIOS_ENTRY_POINT_TYPE_32;
>  }
>  
>  DEFINE_I440FX_MACHINE(v8_0, "pc-i440fx-8.0", NULL,
> diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
> index 6155427e48..6b9fd4d537 100644
> --- a/hw/i386/pc_q35.c
> +++ b/hw/i386/pc_q35.c
> @@ -387,10 +387,15 @@ DEFINE_Q35_MACHINE(v8_1, "pc-q35-8.1", NULL,
>  
>  static void pc_q35_8_0_machine_options(MachineClass *m)
>  {
> +    PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
> +
>      pc_q35_8_1_machine_options(m);
>      m->alias = NULL;
>      compat_props_add(m->compat_props, hw_compat_8_0, hw_compat_8_0_len);
>      compat_props_add(m->compat_props, pc_compat_8_0, pc_compat_8_0_len);
> +
> +    /* For pc-q35-8.0 and older, use SMBIOS 2.8 by default */
> +    pcmc->default_smbios_ep_type = SMBIOS_ENTRY_POINT_TYPE_32;
>  }
>  
>  DEFINE_Q35_MACHINE(v8_0, "pc-q35-8.0", NULL,
> diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
> index c661e9cc80..6eec0fc51d 100644
> --- a/include/hw/i386/pc.h
> +++ b/include/hw/i386/pc.h
> @@ -110,6 +110,7 @@ struct PCMachineClass {
>      bool smbios_defaults;
>      bool smbios_legacy_mode;
>      bool smbios_uuid_encoded;
> +    SmbiosEntryPointType default_smbios_ep_type;
>  
>      /* RAM / address space compat: */
>      bool gigabyte_align;
> -- 
> 2.34.1