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Date:   Sun, 20 Feb 2022 18:32:59 -0800
From:   Eric Biggers <ebiggers@kernel.org>
To:     Dominik Brodowski <linux@dominikbrodowski.net>
Cc:     "Jason A . Donenfeld" <Jason@zx2c4.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org
Subject: Re: [PATCH 1/2] random: fix locking in crng_fast_load()
Message-ID: <YhL527P1sEjpu3R2@sol.localdomain>
References: <20220205103458.133386-1-linux@dominikbrodowski.net>
 <20220205103458.133386-2-linux@dominikbrodowski.net>
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On Sat, Feb 05, 2022 at 11:34:57AM +0100, Dominik Brodowski wrote:
> crng_init is protected by primary_crng->lock, so keep holding that lock
> when incrementing crng_init from 0 to 1 in crng_fast_load(). The call to
> pr_notice() can wait until the lock is released; this code path cannot
> be reached twice, as crng_fast_load() aborts early if crng_init > 0.
> 
> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
> ---
>  drivers/char/random.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)

Reviewed-by: Eric Biggers <ebiggers@google.com>

- Eric