linux-kernel - Re: [PATCHv6 01/16] x86/cpu: Enumerate the LASS feature bits

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Message-ID: <20250620182943.GDaFWolxhwogB2tTxb@fat_crate.local>
Date: Fri, 20 Jun 2025 20:29:43 +0200
From: Borislav Petkov <bp@...en8.de>
To: "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>
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	Yian Chen <yian.chen@...el.com>
Subject: Re: [PATCHv6 01/16] x86/cpu: Enumerate the LASS feature bits

On Fri, Jun 20, 2025 at 08:33:36PM +0300, Kirill A. Shutemov wrote:
> What is current policy around it ?

Documentation/arch/x86/cpuinfo.rst

> I think it is useful to advertise security features in cpuinfo.

Because who's going to consume them?

Don't get me wrong - I am trying to see whether the whole use case for this is
well thought out. Because it becomes an ABI.

But if no one is going to use it, why bother?

Arguably, for this thing the argument would be - as it is put in that file
above:

"So, the current use of /proc/cpuinfo is to show features which the
kernel has *enabled* and *supports*."

as it has been enabled by machinery.

So that's ok. I'm just making sure we're on the same page and you're not
aiming at something completely different with this.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette