linux-kernel - Re: [PATCH v2 1/2] x86/fpu: Extend kernel_fpu_begin

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Message-ID: <875xvmnlzs.ffs@tglx>
Date: Fri, 10 May 2024 09:51:03 +0200
From: Thomas Gleixner <tglx@...utronix.de>
To: Dave Hansen <dave.hansen@...el.com>, "Chang S. Bae"
 <chang.seok.bae@...el.com>, linux-kernel@...r.kernel.org
Cc: x86@...nel.org, platform-driver-x86@...r.kernel.org, mingo@...hat.com,
 bp@...en8.de, dave.hansen@...ux.intel.com, hdegoede@...hat.com,
 ilpo.jarvinen@...ux.intel.com, tony.luck@...el.com, ashok.raj@...el.com,
 jithu.joseph@...el.com
Subject: Re: [PATCH v2 1/2] x86/fpu: Extend kernel_fpu_begin_mask() to
 initialize AMX state

On Thu, May 09 2024 at 10:36, Dave Hansen wrote:
> Three lines of code:
>
> 	1. IFS declares its need to own the FPU for a moment, like any
> 	   other kernel_fpu_begin() user.  It's not a special snowflake.
> 	   It is boring.
> 	2. IFS zaps the FPU state
> 	3. IFS gives up the FPU
>
> Am I out of my mind?  What am I missing?  Why bother with _anything_
> more complicated than this?

Right. Keep it simple :)