linux-kernel - Re: [patch V2 18/52] x86/fpu: Get rid of using_compacted

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Message-ID: <YMs5PGxFcmt46H47@zn.tnic>
Date:   Thu, 17 Jun 2021 13:59:56 +0200
From:   Borislav Petkov <bp@...e.de>
To:     Thomas Gleixner <tglx@...utronix.de>
Cc:     LKML <linux-kernel@...r.kernel.org>,
        Andy Lutomirski <luto@...nel.org>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        Fenghua Yu <fenghua.yu@...el.com>,
        Tony Luck <tony.luck@...el.com>,
        Yu-cheng Yu <yu-cheng.yu@...el.com>,
        Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
        Peter Zijlstra <peterz@...radead.org>,
        Kan Liang <kan.liang@...ux.intel.com>
Subject: Re: [patch V2 18/52] x86/fpu: Get rid of using_compacted_format()

On Mon, Jun 14, 2021 at 05:44:26PM +0200, Thomas Gleixner wrote:
> @@ -590,9 +576,9 @@ static void do_extra_xstate_size_checks(
>  		check_xstate_against_struct(i);
>  		/*
>  		 * Supervisor state components can be managed only by
> -		 * XSAVES, which is compacted-format only.
> +		 * XSAVES.
>  		 */
> -		if (!using_compacted_format())
> +		if (!static_cpu_has(X86_FEATURE_XSAVES))
>  			XSTATE_WARN_ON(xfeature_is_supervisor(i));
>  
>  		/* Align from the end of the previous feature */
> @@ -602,9 +588,9 @@ static void do_extra_xstate_size_checks(
>  		 * The offset of a given state in the non-compacted
>  		 * format is given to us in a CPUID leaf.  We check
>  		 * them for being ordered (increasing offsets) in
> -		 * setup_xstate_features().
> +		 * setup_xstate_features(). XSAVES uses compacted format.
>  		 */
> -		if (!using_compacted_format())
> +		if (!static_cpu_has(X86_FEATURE_XSAVES))

both: cpu_feature_enabled()

and yes, I have complained about that one in the past so good riddance.

Reviewed-by: Borislav Petkov <bp@...e.de>

Btw, that patch looks like it could be moved to the beginning of the
patchset, right after the urgent fixes as it is an independent cleanup.

Thx.

-- 
Regards/Gruss,
    Boris.

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