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Subject: Re: [PATCH v2 9/9] x86/xsaves: Re-enable XSAVES
To: Yu-cheng Yu <yu-cheng.yu@intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, linux-kernel@vger.kernel.org
References: <cover.1456420312.git.yu-cheng.yu@intel.com>
 <8687eb3f43f4a2a4cc2c21f38c5f420631662fd3.1456420312.git.yu-cheng.yu@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>, Borislav Petkov <bp@suse.de>,
        Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>,
        "Ravi V. Shankar" <ravi.v.shankar@intel.com>,
        Fenghua Yu <fenghua.yu@intel.com>
From: Dave Hansen <dave.hansen@linux.intel.com>
Message-ID: <56CF6573.1040604@linux.intel.com>
Date: Thu, 25 Feb 2016 12:34:59 -0800
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On 02/25/2016 12:26 PM, Yu-cheng Yu wrote:
> -	 * ( This is easy to backport while we are fixing
> -	 *   XSAVES* support. )
> +	 * Most recent CPUs supporting XSAVES can run 64-bit mode.
> +	 * Enable XSAVES for 64-bit.
>  	 */
> -	setup_clear_cpu_cap(X86_FEATURE_XSAVES);
> +	if (!config_enabled(CONFIG_X86_64))
> +		setup_clear_cpu_cap(X86_FEATURE_XSAVES);
>  }

Is this intended to be permanent?  If so, we would not be able to
support any future supervisor features on 32-bit.