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Date:   Thu, 13 Oct 2022 21:26:07 -0700
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Subject: Re: [PATCH] x86/fpu: Remove dynamic features from xcomp_bv for
 init_fpstate
Content-Language: en-CA
To:     "Yao, Yuan" <yuan.yao@intel.com>,
        "Hansen, Dave" <dave.hansen@intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
CC:     "x86@kernel.org" <x86@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>
References: <20221011222425.866137-1-dave.hansen@linux.intel.com>
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From:   "Chang S. Bae" <chang.seok.bae@intel.com>
In-Reply-To: <BYAPR11MB3717D733EC448197D0321FF695249@BYAPR11MB3717.namprd11.prod.outlook.com>
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On 10/13/2022 9:10 PM, Yao, Yuan wrote:
> 
> Does init_fpstate saves the "init" state for all non-dynamic components in its buffer ? 

For legacy states :)

	 * ... But doing so is a pointless exercise because most
	 * components have an all zeros init state except for the legacy
	 * ones (FP and SSE).

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/x86/kernel/fpu/xstate.c#n379

Thanks,
Chang