From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B12A0C43334 for ; Wed, 6 Jul 2022 16:44:08 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4LdQNl0gQ3z3c5g for ; Thu, 7 Jul 2022 02:44:07 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=zytor.com header.i=@zytor.com header.a=rsa-sha256 header.s=2022060401 header.b=uod/87Km; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=zytor.com (client-ip=198.137.202.136; helo=mail.zytor.com; envelope-from=hpa@zytor.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=zytor.com header.i=@zytor.com header.a=rsa-sha256 header.s=2022060401 header.b=uod/87Km; dkim-atps=neutral Received: from mail.zytor.com (terminus.zytor.com [198.137.202.136]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4LdQN02SSWz3c0H for ; Thu, 7 Jul 2022 02:43:26 +1000 (AEST) Received: from [127.0.0.1] ([73.223.250.219]) (authenticated bits=0) by mail.zytor.com (8.17.1/8.15.2) with ESMTPSA id 266Ggp781236933 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO); Wed, 6 Jul 2022 09:42:51 -0700 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.zytor.com 266Ggp781236933 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2022060401; t=1657125775; bh=zQoEvTxnDh6zWBd1c1ezKVw870QaKisAdMJsMEZ0XiI=; h=Date:From:To:CC:Subject:In-Reply-To:References:From; b=uod/87KmlxnlFtaMoLSH+a3zy87aEMycqPjViqWSmbrvXTDJePOvAvh4NdfmXjyOo /nZjEuDksvqEeMFeyvv3nNTJaLGMHrWkIQZOgcNcM3isnB2T3CVCzQYI731tr8Huo6 7H2oEO54ACpyb6iUmo0L2mcfUpp9aQvoLhDCxBbnm5v+FW3EtXCUH3XJpeWQHzzhV/ eulgCmnqbY02rNDoS+WZNu79Fosli2i61lGLIGLfx3DdGltUdPqnFp6O9bBcgBWMam 2PXfzTFX5aQgK0eGmJfiwxbYGBVaUAWny3Ktqh+1F919S48/9ocINv7En1vi36fb0T n+NARfx8eOcGg== Date: Wed, 06 Jul 2022 09:42:49 -0700 From: "H. Peter Anvin" To: Borislav Petkov Subject: Re: [PATCH] random: remove CONFIG_ARCH_RANDOM and "nordrand" User-Agent: K-9 Mail for Android In-Reply-To: References: <20220705190121.293703-1-Jason@zx2c4.com> <11C903CC-22A7-48EE-AD63-E71CC8D28B88@zytor.com> <805B66CB-D847-4547-B6EE-C4FB72B75765@zytor.com> Message-ID: <0A608F00-CDC0-494E-AC57-69BA0E3F547F@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-s390@vger.kernel.org, "Jason A. Donenfeld" , Arnd Bergmann , Will Deacon , Greg Kroah-Hartman , Catalin Marinas , Heiko Carstens , x86@kernel.org, linux-kernel@vger.kernel.org, Alexander Gordeev , linuxppc-dev@lists.ozlabs.org, Thomas Gleixner , linux-arm-kernel@lists.infradead.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On July 6, 2022 5:23:31 AM PDT, Borislav Petkov wrote: >On Tue, Jul 05, 2022 at 04:11:45PM -0700, H=2E Peter Anvin wrote: >> What I'm wondering is if we shouldn't be simply instrument *every* >> invocation, and set the trust to zero if we ever trip it=2E > >I guess you can add some logic to rdrand_long() to sanity-check what it >returns=2E=2E=2E > >But would that be worth the effort? > I think doing it centrally, as non-arch-specific code, and letting it subs= ume ad hoc checks for known failure conditions could be a win=2E