Re: [RFC PATCH v2] tools/x86: add kcpuid tool to show raw CPU features

[Arvind Sankar]

On Fri, Sep 25, 2020 at 07:16:31PM +0200, Borislav Petkov wrote:
> On Wed, Sep 23, 2020 at 10:45:29AM +0800, Feng Tang wrote:
> > > Rather than a tool, would additional file(s) in, say,
> > > /sys/devices/system/cpu/cpu<n> be nicer? They could show the raw CPUID
> > > features, one file per leaf or sub-leaf, maybe even along with whether
> > > they were disabled at boot-time.
> > 
> > My thought is we already have in-kernel powerful /proc/cpuinfo, while 
> > a user space tool could be more flexible for text parsing/layout, and
> > show different info on user's demand/options.
> 
> The important thing here is that a separate tool would be decoupled from
> the kernel and thus will be independent from it, i.e., you can get the
> tool and run it without having to install a new kernel.
> 
> And with the CPUID leafs specified in a text file, you won't even need
> to update the tool even - just cpuid.txt. It can't get any better than
> that.
> 
> -- 
> Regards/Gruss,
>     Boris.
> 
> https://people.kernel.org/tglx/notes-about-netiquette

Ok. Another suggestion: while designing the format for the cpuid.txt
file, would it be possible to include enough information for
cpufeatures.h to be auto-generated from it?