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Date: Thu, 1 Oct 2015 13:50:24 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Dave Hansen <dave@sr71.net>
cc: borntraeger@de.ibm.com, x86@kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, dave.hansen@linux.intel.com
Subject: Re: [PATCH 05/25] x86, pkey: add PKRU xsave fields and data
 structure(s)
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On Mon, 28 Sep 2015, Dave Hansen wrote:
> +/*
> + * State component 9: 32-bit PKRU register.
> + */
> +struct pkru {
> +	u32 pkru;
> +} __packed;
> +
> +struct pkru_state {
> +	union {
> +		struct pkru		pkru;
> +		u8			pad_to_8_bytes[8];
> +	};

Why do you need two structs?

    struct pkru_state {
    	   u32 pkru;
	   u32 pad;
    }

should be sufficient. So instead of

       xsave.pkru_state.pkru.pkru

you get the more obvious

       xsave.pkru_state.pkru

Hmm?

Thanks,

	tglx