Re: [Qemu-devel] [PATCH 13/13] x86/cpuid: Update qemu64/32 CPU models

[Jamie Lokier <jamie@shareable.org>]

Andre Przywara wrote:
> Since we now have a real TCG feature set, use it to describe the
> artificial qemu CPUs (both 64 and 32-bit). If new features are added
> to TCG, the capability of qemu64/32 will automatically be adjusted.
> 
> Signed-off-by: Andre Przywara <andre.przywara@amd.com>

> -        .features = PPRO_FEATURES | 
> -        /* these features are needed for Win64 and aren't fully implemented */
> -            CPUID_MTRR | CPUID_CLFLUSH | CPUID_MCA |
> -        /* this feature is needed for Solaris and isn't fully implemented */
> -            CPUID_PSE36,
> -        .ext_features = CPUID_EXT_SSE3 | CPUID_EXT_CX16 | CPUID_EXT_POPCNT,
> -        .ext2_features = (PPRO_FEATURES & EXT2_FEATURE_MASK) | 
> -            CPUID_EXT2_LM | CPUID_EXT2_SYSCALL | CPUID_EXT2_NX,
> -        .ext3_features = CPUID_EXT3_LAHF_LM | CPUID_EXT3_SVM |
> -            CPUID_EXT3_ABM | CPUID_EXT3_SSE4A,

Those comments seem to have disappeared.  Are they useful - or even correct any more?

> +        .features = TCG_FEATURES,
> +        .ext_features = TCG_EXT_FEATURES,
> +        /* 3DNow! is deprecated, so leave it out of the default feature set */
> +        .ext2_features = (TCG_EXT2_FEATURES | EXT2_FEATURES_64) &
> +                        ~(CPUID_EXT2_3DNOW | CPUID_EXT2_3DNOWEXT),
> +        .ext3_features = TCG_EXT3_FEATURES,

3DNow! is an old capability, but why is that a reason to single it out
for omission?

Is there any harm in it being enabled?

-- Jamie