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Date: Fri, 27 Nov 2015 10:51:16 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Dave Hansen <dave@sr71.net>
cc: linux-kernel@vger.kernel.org, x86@kernel.org, dave.hansen@linux.intel.com
Subject: Re: [PATCH 17/37] x86, pkeys: add functions to fetch PKRU
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On Mon, 16 Nov 2015, Dave Hansen wrote:
> +#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
> +static inline u32 __read_pkru(void)
> +{
> +	unsigned int eax, edx;
> +	unsigned int ecx = 0;
> +	unsigned int pkru;
> +
> +	asm volatile(".byte 0x0f,0x01,0xee\n\t"
> +		     : "=a" (eax), "=d" (edx)
> +		     : "c" (ecx));
> +	pkru = eax;
> +	return pkru;

Wouldn't a simple 'return eax;' be sufficient?

Thanks,

	tglx