Re: [Qemu-devel] [PATCH v16 2/3] i386: Enable TOPOEXT feature on AMD EPYC CPU

[Eduardo Habkost <ehabkost@redhat.com>]

On Tue, Jun 19, 2018 at 05:31:58PM -0400, Babu Moger wrote:
> Enable TOPOEXT feature on EPYC CPU. This is required to support
> hyperthreading on VM guests. Also extend xlevel to 0x8000001E.
> 
> Disable topoext on PC_COMPAT_2_12 and keep xlevel 0x8000000a.
> 
> Signed-off-by: Babu Moger <babu.moger@amd.com>
> ---
>  include/hw/i386/pc.h |  8 ++++++++
>  target/i386/cpu.c    | 10 ++++++----
>  2 files changed, 14 insertions(+), 4 deletions(-)
> 
> diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
> index fc8dedc..d0ebeb9 100644
> --- a/include/hw/i386/pc.h
> +++ b/include/hw/i386/pc.h
> @@ -303,6 +303,14 @@ bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *);
>          .driver   = TYPE_X86_CPU,\
>          .property = "legacy-cache",\
>          .value    = "on",\
> +    },{\
> +        .driver   = TYPE_X86_CPU,\
> +        .property = "topoext",\
> +        .value    = "off",\
> +    },{\
> +        .driver   = "EPYC-" TYPE_X86_CPU,\
> +        .property = "xlevel",\
> +        .value    = stringify(0x8000000a),\
>      },

EPYC-IBPB is missing, I will add it when committing.  Thanks!

-- 
Eduardo