From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755947AbbESO2B (ORCPT ); Tue, 19 May 2015 10:28:01 -0400 Received: from mail.eperm.de ([89.247.134.16]:57966 "EHLO mail.eperm.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755524AbbESO15 (ORCPT ); Tue, 19 May 2015 10:27:57 -0400 From: Stephan Mueller To: Herbert Xu Cc: "Theodore Ts'o" , pebolle@tiscali.nl, andreas.steffen@strongswan.org, sandyinchina@gmail.com, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org Subject: Re: [PATCH v6 1/5] random: Blocking API for accessing nonblocking_pool Date: Tue, 19 May 2015 16:27:54 +0200 Message-ID: <1637466.ZUdUCXWXVs@tauon> User-Agent: KMail/4.14.6 (Linux/3.19.5-200.fc21.x86_64; KDE/4.14.6; x86_64; ; ) In-Reply-To: <20150519141805.GA32663@gondor.apana.org.au> References: <1921857.OvxEu6y28S@tachyon.chronox.de> <20150519135028.GC20421@thunk.org> <20150519141805.GA32663@gondor.apana.org.au> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Dienstag, 19. Mai 2015, 22:18:05 schrieb Herbert Xu: Hi Herbert, >On Tue, May 19, 2015 at 09:50:28AM -0400, Theodore Ts'o wrote: >> Finally, this is only going to block *once*, when the system is >> initially botting up. Why is it so important that we get the >> asynchronous nature of this right, and why can't we solve it simply by >> just simply doing the work in a workqueue, with a completion barrier >> getting triggered once /dev/random initializes itself, and just simply >> blocking the module unload until /dev/random is initialized? > >I guess I'm still thinking of the old work queue code before >Tejun's cmwq work. Yes blocking in a work queue should be fine >as there is usually just one DRBG instance. The current modification with patch 1 to random.c is the smallest change to date. Is that then appropriate? Herbert, based on your comment now, would the currently discussed patch with waiting in the work queue in patch 3 appropriate? Or what would you like to see changed? Ciao Stephan