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Date: Mon, 16 Jan 2017 14:59:11 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Vikas Shivappa <vikas.shivappa@linux.intel.com>
cc: vikas.shivappa@intel.com, linux-kernel@vger.kernel.org, x86@kernel.org,
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        h.peter.anvin@intel.com
Subject: Re: [PATCH 4/8] x86/intel_rdt/mba: Memory b/w allocation feature
 detect
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References: <1484076788-25385-1-git-send-email-vikas.shivappa@linux.intel.com> <1484076788-25385-5-git-send-email-vikas.shivappa@linux.intel.com>
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On Tue, 10 Jan 2017, Vikas Shivappa wrote:

> Detect MBA feature if CPUID.(EAX=10H, ECX=0):EBX.L2[bit 3] = 1.
> Add supporting data structures to detect feature details which is done
> in later patch using CPUID with EAX=10H, ECX= 3.

So why is the $subject of this patch claiming that it provides the feature
detection?

> -/* CPUID.(EAX=10H, ECX=ResID=1).EDX */
> +/* CPUID.(EAX=10H, ECX=ResID=3).EAX */
> +union cpuid_0x10_3_eax {
> +	struct {
> +		unsigned int max_delay:12;
> +	} split;

And the point of this struct is?

> +	unsigned int full;
> +};

> +	if (boot_cpu_has(X86_FEATURE_MBA)) {
> +		ret = true;
> +	}

Pointless brackets.

Thanks,

	tglx