linux-kernel - Re: [PATCH v3 04/37] x86/cpufeatures: Enable CET CR4 bit for shadow stack

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Date:   Mon, 7 Nov 2022 20:30:57 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
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Subject: Re: [PATCH v3 04/37] x86/cpufeatures: Enable CET CR4 bit for shadow
 stack

On Mon, Nov 07, 2022 at 07:19:21PM +0000, Edgecombe, Rick P wrote:
> There was at one point, but there was a suggestion to remove in favor
> of clearcpuid. I can add it back.

Sounds like I need to school that "suggestor" about clearcpuid. :)

For example, when doing this:

  1625c833db93 ("x86/cpu: Allow feature bit names from /proc/cpuinfo in clearcpuid=")

I even managed to prevent the kernel from booting. So clearcpuid= is
definitely not for general consumption.

So as said, please remove it from your whole patchset's text.

Thx.

-- 
Regards/Gruss,
    Boris.

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