linux-kernel - Re: [PATCH v10 15/15] x86/cpu: Enable LASS by default during CPU initialization

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Message-ID: <d34857c2f90bf57db491c89118c9e759abf0fb2c.camel@intel.com>
Date: Tue, 7 Oct 2025 18:42:48 +0000
From: "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
To: "Mehta, Sohil" <sohil.mehta@...el.com>, "tglx@...utronix.de"
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Subject: Re: [PATCH v10 15/15] x86/cpu: Enable LASS by default during CPU
 initialization

On Mon, 2025-10-06 at 23:51 -0700, Sohil Mehta wrote:
> Linear Address Space Separation (LASS) mitigates a class of side-channel
> attacks that rely on speculative access across the user/kernel boundary.
> Enable it by default if the platform supports it.
> 
> While at it, remove the comment above the SMAP/SMEP/UMIP/LASS setup
> instead of updating it, as the whole sequence is quite self-explanatory.
> 
> Signed-off-by: Sohil Mehta <sohil.mehta@...el.com>

Reviewed-by: Rick Edgecombe <rick.p.edgecombe@...el.com>