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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 439B4C433F5 for ; Thu, 10 Feb 2022 16:57:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244940AbiBJQ5L (ORCPT ); Thu, 10 Feb 2022 11:57:11 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:39852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244450AbiBJQ5F (ORCPT ); Thu, 10 Feb 2022 11:57:05 -0500 Received: from isilmar-4.linta.de (isilmar-4.linta.de [136.243.71.142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6CDC7EE for ; Thu, 10 Feb 2022 08:57:06 -0800 (PST) X-isilmar-external: YES X-isilmar-external: YES X-isilmar-external: YES Received: from owl.dominikbrodowski.net (owl.brodo.linta [10.2.0.111]) by isilmar-4.linta.de (Postfix) with ESMTPSA id 81A69201352; Thu, 10 Feb 2022 16:57:03 +0000 (UTC) Received: by owl.dominikbrodowski.net (Postfix, from userid 1000) id D0ED48065E; Thu, 10 Feb 2022 17:55:53 +0100 (CET) Date: Thu, 10 Feb 2022 17:55:53 +0100 From: Dominik Brodowski To: "Jason A. Donenfeld" Cc: linux-kernel@vger.kernel.org, Theodore Ts'o Subject: Re: [PATCH 2/2] random: deobfuscate irq u32/u64 contributions Message-ID: References: <20220210160925.156697-1-Jason@zx2c4.com> <20220210160925.156697-3-Jason@zx2c4.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220210160925.156697-3-Jason@zx2c4.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Thu, Feb 10, 2022 at 05:09:25PM +0100 schrieb Jason A. Donenfeld: > In the irq handler, we fill out 16 bytes differently on 32-bit and > 64-bit platforms. Whether or not you like that, it is a matter of fact. > But it might not be a fact you well realized until now, because the code > that loaded the irq info into 4 32-bit words was quite confusing. > Instead, this commit makes everything explicit by having separate > (compile-time) branches for 32-bit and 64-bit machines. In the process, > it exposed a shortcoming in in mix_interrupt_randomness() which we "in in" -> "in" > rectify. Maybe explain the shortcoming in one sentence? I think I spotted it, but... Thanks, Dominik