Re: [Qemu-devel] [PATCH 1/1] i386: Add new model of Cascadelake-Server

[Eduardo Habkost]

On Wed, Sep 19, 2018 at 11:11:22AM +0800, Tao Xu wrote:
> New CPU models mostly inherit features from ancestor Skylake-Server,
> while addin new features: AVX512_VNNI, Intel PT.
> SSBD support for speculative execution
> side channel mitigations.

Comparing to Skylake-Server, the following features are being
added:

CPUID_7_0_EBX_INTEL_PT, CPUID_7_0_ECX_PKU, CPUID_7_0_ECX_OSPKE,
CPUID_7_0_ECX_AVX512VNNI, CPUID_7_0_EDX_SPEC_CTRL,
CPUID_7_0_EDX_SPEC_CTRL_SSBD.

>From that list, only PKU/OSPKE is not mentioned in the commit
message.  Is this intentional?

Is family/model really supposed to be the same as the one on
Skylake-Server?

> 
> Note:
> 
> On Cascadelake, some capabilities (RDCL_NO, IBRS_ALL, RSBA,
> SKIP_L1DFL_VMENTRY and SSB_NO) are enumerated by MSR.
> These features rely on MSR based feature support patch. 
> Will be added later after that patch's in.
> http://lists.nongnu.org/archive/html/qemu-devel/2018-09/msg00074.html
> 
> Signed-off-by: Tao Xu <address@hidden>
> ---
>  target/i386/cpu.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 54 insertions(+)
> 
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index f24295e6e4..670898f32d 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -2386,6 +2386,60 @@ static X86CPUDefinition builtin_x86_defs[] = {
>          .xlevel = 0x80000008,
>          .model_id = "Intel Xeon Processor (Skylake, IBRS)",
>      },
> +    {
> +        .name = "Cascadelake-Server",
> +        .level = 0xd,
> +        .vendor = CPUID_VENDOR_INTEL,
> +        .family = 6,
> +        .model = 85,
> +        .stepping = 5,
> +        .features[FEAT_1_EDX] =
> +            CPUID_VME | CPUID_SSE2 | CPUID_SSE | CPUID_FXSR | CPUID_MMX |
> +            CPUID_CLFLUSH | CPUID_PSE36 | CPUID_PAT | CPUID_CMOV | CPUID_MCA 
> |
> +            CPUID_PGE | CPUID_MTRR | CPUID_SEP | CPUID_APIC | CPUID_CX8 |
> +            CPUID_MCE | CPUID_PAE | CPUID_MSR | CPUID_TSC | CPUID_PSE |
> +            CPUID_DE | CPUID_FP87,
> +        .features[FEAT_1_ECX] =
> +            CPUID_EXT_AVX | CPUID_EXT_XSAVE | CPUID_EXT_AES |
> +            CPUID_EXT_POPCNT | CPUID_EXT_X2APIC | CPUID_EXT_SSE42 |
> +            CPUID_EXT_SSE41 | CPUID_EXT_CX16 | CPUID_EXT_SSSE3 |
> +            CPUID_EXT_PCLMULQDQ | CPUID_EXT_SSE3 |
> +            CPUID_EXT_TSC_DEADLINE_TIMER | CPUID_EXT_FMA | CPUID_EXT_MOVBE |
> +            CPUID_EXT_PCID | CPUID_EXT_F16C | CPUID_EXT_RDRAND,
> +        .features[FEAT_8000_0001_EDX] =
> +            CPUID_EXT2_LM | CPUID_EXT2_PDPE1GB | CPUID_EXT2_RDTSCP |
> +            CPUID_EXT2_NX | CPUID_EXT2_SYSCALL,
> +        .features[FEAT_8000_0001_ECX] =
> +            CPUID_EXT3_ABM | CPUID_EXT3_LAHF_LM | CPUID_EXT3_3DNOWPREFETCH,
> +        .features[FEAT_7_0_EBX] =
> +            CPUID_7_0_EBX_FSGSBASE | CPUID_7_0_EBX_BMI1 |
> +            CPUID_7_0_EBX_HLE | CPUID_7_0_EBX_AVX2 | CPUID_7_0_EBX_SMEP |
> +            CPUID_7_0_EBX_BMI2 | CPUID_7_0_EBX_ERMS | CPUID_7_0_EBX_INVPCID |
> +            CPUID_7_0_EBX_RTM | CPUID_7_0_EBX_RDSEED | CPUID_7_0_EBX_ADX |
> +            CPUID_7_0_EBX_SMAP | CPUID_7_0_EBX_MPX | CPUID_7_0_EBX_CLWB |
> +            CPUID_7_0_EBX_AVX512F | CPUID_7_0_EBX_AVX512DQ |
> +            CPUID_7_0_EBX_AVX512BW | CPUID_7_0_EBX_AVX512CD |
> +            CPUID_7_0_EBX_AVX512VL | CPUID_7_0_EBX_CLFLUSHOPT |
> +            CPUID_7_0_EBX_INTEL_PT,
> +        .features[FEAT_7_0_ECX] =
> +            CPUID_7_0_ECX_PKU | CPUID_7_0_ECX_OSPKE |
> +            CPUID_7_0_ECX_AVX512VNNI,
> +        .features[FEAT_7_0_EDX] =
> +            CPUID_7_0_EDX_SPEC_CTRL | CPUID_7_0_EDX_SPEC_CTRL_SSBD,
> +        /* Missing: XSAVES (not supported by some Linux versions,
> +                * including v4.1 to v4.12).
> +                * KVM doesn't yet expose any XSAVES state save component,
> +                * and the only one defined in Skylake (processor tracing)
> +                * probably will block migration anyway.
> +                */
> +        .features[FEAT_XSAVE] =
> +            CPUID_XSAVE_XSAVEOPT | CPUID_XSAVE_XSAVEC |
> +            CPUID_XSAVE_XGETBV1,
> +        .features[FEAT_6_EAX] =
> +            CPUID_6_EAX_ARAT,
> +        .xlevel = 0x80000008,
> +        .model_id = "Intel Xeon Processor (Cascadelake)",
> +    },
>      {
>          .name = "Icelake-Client",
>          .level = 0xd,
> -- 
> 2.17.1
> 
> 

-- 
Eduardo