From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BB73134D901; Wed, 10 Jun 2026 18:39:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781116745; cv=none; b=rnwaKcR8FhV+BrjtLDgCylkEtFQgG8LiEU8aips/VEbqFtlMFBjCFNyfOvOHdIqWdqx4CFCDrn1Dvfc7/ymvaYJIVE+QPEs9V4SHNr6MzVu04UbambkZigSG2EAA3DR1O7OzCnLGQy48p+hq2bYyHO/Hgd/JWSuk22Aj5BzmmFQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781116745; c=relaxed/simple; bh=GxMar0oLEIQoe7sHtEEfoKoR0HEcjBy+/l3pVm1wND8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=mFCVGnNzWYgejpEOzB4ZPX5+64K0DQixJ6qnEI5vGhajbKvHT9JcHTy1aMf8h6LJl/tAQ6a61KZph0iZ5EGqWmGzMWd5YRDn07GCUC97tNKS32SmxH/nk9aLc/MQe2jv7VSaImiqYv8ixMsTGTu1+4ihpZ0IN7KSyaHqcyhU86Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=L1ObFPr2; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="L1ObFPr2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 12DC01F00893; Wed, 10 Jun 2026 18:39:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781116744; bh=4o1VtWCXoWoxZBd6EawCUnJfQ/1lp18t/RARZHM0h5E=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=L1ObFPr2OvgTYrOIIO4/YtP6lSqMh682GiOhOkJWrOkn11BH1KN8+D4dLayTtyAQk OCKltKKSoaFudM5UTbZ+sDqvJaKgF28LSWLxitUx48re7IN69YoiqhAv4HE7aKihIh +XbGlAD2J3OJ+EZixK+Wo8iw8K4CDmoLOe6pazU99tWs+FmU0aQMs8QPKLuPd74MHr w9hezWha/VMuYab5un8ehjztSILHjkRN9dG/0/4SoZ9dQxe4+t+NbkaUDyKD2FemYq IwsHPk29AfT229gyPnvy6kNFwH4JnlrUTfsyf8BymvScuBdBtvXClCOzC7Z+Q/4Ui3 qm9lGdnlcUozw== Date: Wed, 10 Jun 2026 18:39:02 +0000 From: Eric Biggers To: Peter Griffin Cc: linux-crypto@vger.kernel.org, Herbert Xu , linux-samsung-soc@vger.kernel.org, Krzysztof Kozlowski , Alim Akhtar , linux-kernel@vger.kernel.org Subject: Re: [PATCH] crypto: exynos-rng - Remove exynos-rng driver Message-ID: <20260610183902.GA1158828@google.com> References: <20260531175932.32171-1-ebiggers@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Jun 10, 2026 at 03:46:54PM +0100, Peter Griffin wrote: > Hi Eric, > > On Sun, 31 May 2026 at 19:02, Eric Biggers wrote: > > > > This driver has no purpose. It doesn't feed into the Linux RNG, nor > > does it implement the hwrng interface. It is accessible only via the > > "rng" algorithm type of AF_ALG, which isn't used in practice. Everyone > > uses either the Linux RNG, or rarely /dev/hwrng. > > > > Moreover, this is a PRNG whose only source of entropy is the 160-bit > > seed the user passes in. So this can be used only by a user who already > > has a source of cryptographically secure random numbers, such as > > /dev/random. Which they can, and do, just use in the first place. > > > > Just remove this driver. There's no need to keep useless code around. > > > > Note that the other crypto_rng drivers in drivers/crypto/ are similarly > > unused and are being removed too. This commit just handles exynos-rng. > > > > Signed-off-by: Eric Biggers > > --- > > If the driver is being removed, should the binding documentation for > this driver not also be deleted (see > Documentation/devicetree/bindings/rng/samsung,exynos4-rng.yaml)? > > Peter In other discussions I've been told that devicetree bindings are hardware descriptions that should still exist even if there is no driver. It doesn't make a lot of sense, but it seems to be what the devicetree people want. I expect there would be objections to removing this binding. - Eric