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Date:   Wed, 16 Nov 2022 12:19:38 +0100
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
To:     Robert Elliott <elliott@hpe.com>
Cc:     herbert@gondor.apana.org.au, davem@davemloft.net,
        tim.c.chen@linux.intel.com, ap420073@gmail.com, ardb@kernel.org,
        David.Laight@ACULAB.COM, ebiggers@kernel.org,
        linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4 17/24] crypto: x86/poly - load based on CPU features
Message-ID: <Y3THSmvuZlq2+hky@zx2c4.com>
References: <20221103042740.6556-1-elliott@hpe.com>
 <20221116041342.3841-1-elliott@hpe.com>
 <20221116041342.3841-18-elliott@hpe.com>
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On Tue, Nov 15, 2022 at 10:13:35PM -0600, Robert Elliott wrote:
> +static const struct x86_cpu_id module_cpu_ids[] = {
> +	X86_MATCH_FEATURE(X86_FEATURE_ANY, NULL),
> +	{}
> +};
> +MODULE_DEVICE_TABLE(x86cpu, module_cpu_ids);
> +
>  static int __init poly1305_simd_mod_init(void)
>  {
> +	if (!x86_match_cpu(module_cpu_ids))
> +		return -ENODEV;

What exactly does this accomplish? Isn't this just a no-op?

Jason