On Wed, Sep 02, 2020 at 05:40:18PM +0200, Borislav Petkov wrote:
> On Thu, Aug 27, 2020 at 03:49:03PM +0800, Feng Tang wrote:
> > output of the tool
> > ------------------
> >
> > CPUID leafs total: 28
> >
> > cpu family : 6
> > model : 13
> > stepping : 7
>
> Yeah, this should dump model etc and those numbers should be in hex and
> additionally in dec if people prefer them.
Ok
> > CPU features
> > ------------
> > sse3
> > pclmlqdq
> > dtes64
> > mwait
> > ds_cpl
> > vmx
> > smx
> > fpu
> > ...
>
> I guess that's good for grepping. With a lot of leafs, leaf output
> should probably be controlled by cmdline opts.
Will add input option for specific leafs or all.
> > tools/arch/x86/tools/kcpuid/Makefile | 21 ++
> > tools/arch/x86/tools/kcpuid/kcpuid.c | 422
> > +++++++++++++++++++++++++++++++++++
> > 2 files changed, 443 insertions(+)
> > create mode 100644 tools/arch/x86/tools/kcpuid/Makefile
> > create mode 100644 tools/arch/x86/tools/kcpuid/kcpuid.c
>
> Let's drop the second "tools" from the path:
>
> tools/arch/x86/kcpuid/Makefile
> tools/arch/x86/kcpuid/kcpuid.c
Will do.
> > +struct reg_01_a {
> > + u32 stepping: 4; /* bit 0 */
> > + u32 model: 4;
> > + u32 family: 4;
> > + u32 type: 2;
> > + u32 pad1: 2;
> > + u32 model_ext: 4; /* bit 16 */
> > + u32 family_ext: 8;
> > +};
>
> Yeah, instead of defining a separate struct for each leaf I think it
> would be smarter/better to have a text file in a machine parseable
> format which defines your leafs.
>
> When you need to add a new leaf, you simply extend the text file and the
> tool parses it anew and has its all CPUID info uptodate. This way you
> won't even have to recompile it. Adding new CPUID leafs would be adding new
> lines to the file.
>
> For example:
>
> LEAF<num>,SUBLEAF<num>,[EAX,EBX,ECX,EDX]{[width]<Mnemonic>|<Long text>,...}
>
> LEAF07,SUBLEAF00,EAX{[31:0]max_value|Max input value for supported subleafs}
> LEAF07,SUBLEAF00,EBX{[0]FSGSBASE|RDFSBASE/RDGSBASE/WRFSBASE/WRGSBASE if 1.,
> [1]TSC_ADJUST|IA32_TSC_ADJUST MSR is supported if 1.,
> [2]SGX|Supports Intel® Software Guard Extensions (Intel®
> SGX Extensions) if 1.,
> ...
> }
> LEAF07,SUBLEAF00,ECX{[0]PREFETCHWT1|(Intel® Xeon PhiTM only.),
> [1]AVX512_VBMI|,
> ...
>
> This is just a dumb attempt but I hope it comes across where I'm getting
> with this.
Will check this, and further study the different bits you, Peter and Dave
have mentioned in the discussion.
Thank you all for the review and suggestions!
- Feng
