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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 268BDC3A59F for ; Thu, 29 Aug 2019 13:37:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EC5A52189D for ; Thu, 29 Aug 2019 13:37:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727590AbfH2Nhn (ORCPT ); Thu, 29 Aug 2019 09:37:43 -0400 Received: from s3.sipsolutions.net ([144.76.43.62]:35770 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726985AbfH2Nhm (ORCPT ); Thu, 29 Aug 2019 09:37:42 -0400 Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.92.1) (envelope-from ) id 1i3KcH-000130-QZ; Thu, 29 Aug 2019 15:37:33 +0200 Message-ID: <696734afb27182d7a1a9218dd3cfa01f47a76093.camel@sipsolutions.net> Subject: Re: [PATCH] um: Rewrite host RNG driver. From: Johannes Berg To: Alexander Neville , Richard Weinberger , Anton Ivanov , linux-um@lists.infradead.org, linux-kernel@vger.kernel.org Date: Thu, 29 Aug 2019 15:37:32 +0200 In-Reply-To: <20190828204609.02a7ff70@TheDarkness> References: <20190828204609.02a7ff70@TheDarkness> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.30.5 (3.30.5-1.fc29) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2019-08-28 at 21:44 -0400, Alexander Neville wrote: > The old driver had a bug that would cause it to outright stop working if > the host's /dev/random were to block. Instead of trying to track down > the cause of said bug, rewriting it from scratch turned out to be a much > better option as it came with a few benefits: > > - The new driver properly registers itself as an hardware RNG. > > - The code is simpler and therefore easier to maintain. > > - It serves as a minimal example of writing a hardware RNG driver. > > I also edited the Kconfig symbol to bring it up to more modern > standards. I realize that it's still easier to use, but theoretically you could just use the virtio implementation, and use that driver with a suitable small vhost device implementation. :-) johannes