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

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Message-ID: <BAD6BC84-0554-412D-B587-9F6EA5D55746@zytor.com>
Date: Mon, 23 Jun 2025 19:03:03 -0700
From: "H. Peter Anvin" <hpa@...or.com>
To: "Luck, Tony" <tony.luck@...el.com>, "Hansen, Dave" <dave.hansen@...el.com>,
        "Mehta, Sohil" <sohil.mehta@...el.com>,
        "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
        Dave Hansen <dave.hansen@...ux.intel.com>
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Subject: RE: [PATCHv6 01/16] x86/cpu: Enumerate the LASS feature bits

On June 23, 2025 5:10:50 PM PDT, "Luck, Tony" <tony.luck@...el.com> wrote:
>> Are we actually doing patching on more than one CPU at a time?
>
>We could call static_key_enable()/static_key_disable() for different
>keys at the same time from multiple CPUs.
>
>Do we actually do that? Probably not.
>
>-Tony
>

But does it actually *work*?