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Date:   Sat, 5 Oct 2019 00:26:03 +1000
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Laurent Vivier <lvivier@redhat.com>
Cc:     linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org,
        Matt Mackall <mpm@selenic.com>
Subject: Re: [PATCH] hw_random: move add_early_randomness() out of rng_mutex
Message-ID: <20191004142603.GA29787@gondor.apana.org.au>
References: <20190912133022.14870-1-lvivier@redhat.com>
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On Thu, Sep 12, 2019 at 03:30:22PM +0200, Laurent Vivier wrote:
>
> @@ -496,19 +510,24 @@ int hwrng_register(struct hwrng *rng)
>  			goto out_unlock;
>  	}
>  
> -	if (old_rng && !rng->init) {
> +	new_rng = rng;
> +	kref_get(&new_rng->ref);
> +out_unlock:
> +	mutex_unlock(&rng_mutex);
> +
> +	if (new_rng) {
> +		if (new_rng != old_rng || !rng->init) {

Is this really supposed to be || instead of &&?

>  		/*
>  		 * Use a new device's input to add some randomness to
>  		 * the system.  If this rng device isn't going to be
>  		 * used right away, its init function hasn't been
> -		 * called yet; so only use the randomness from devices
> -		 * that don't need an init callback.
> +		 * called yet by set_current_rng(); so only use the
> +		 * randomness from devices that don't need an init callback
>  		 */
> -		add_early_randomness(rng);
> +			add_early_randomness(new_rng);
> +		}
> +		put_rng(new_rng);
>  	}

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt