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From: Thomas Gleixner <tglx@linutronix.de>
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To: Dave Hansen <dave.hansen@intel.com>, "Chang S. Bae"
 <chang.seok.bae@intel.com>, linux-kernel@vger.kernel.org
Cc: x86@kernel.org, platform-driver-x86@vger.kernel.org, mingo@redhat.com,
 bp@alien8.de, dave.hansen@linux.intel.com, hdegoede@redhat.com,
 ilpo.jarvinen@linux.intel.com, tony.luck@intel.com, ashok.raj@intel.com,
 jithu.joseph@intel.com
Subject: Re: [PATCH v2 1/2] x86/fpu: Extend kernel_fpu_begin_mask() to
 initialize AMX state
In-Reply-To: <fde6149c-7ddf-488f-98c0-04f336b7092e@intel.com>
References: <20240430212508.105117-1-chang.seok.bae@intel.com>
 <20240507235344.249103-1-chang.seok.bae@intel.com>
 <20240507235344.249103-2-chang.seok.bae@intel.com>
 <f82879a5-f3ca-436f-8c4a-96d4c5d90354@intel.com>
 <7e589b35-4ff8-43fa-99dd-d3b17f56d3ea@intel.com>
 <fde6149c-7ddf-488f-98c0-04f336b7092e@intel.com>
Date: Fri, 10 May 2024 09:51:03 +0200
Message-ID: <875xvmnlzs.ffs@tglx>
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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 :)