Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262019AbUK3IY4 (ORCPT ); Tue, 30 Nov 2004 03:24:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262017AbUK3IY4 (ORCPT ); Tue, 30 Nov 2004 03:24:56 -0500 Received: from linux01.gwdg.de ([134.76.13.21]:26331 "EHLO linux01.gwdg.de") by vger.kernel.org with ESMTP id S262019AbUK3IXU (ORCPT ); Tue, 30 Nov 2004 03:23:20 -0500 Date: Tue, 30 Nov 2004 09:23:17 +0100 (MET) From: Jan Engelhardt cc: linux-kernel@vger.kernel.org Subject: Re: Concurrent access to /dev/urandom In-Reply-To: <5AC4B64A-4286-11D9-8639-000393ACC76E@mac.com> Message-ID: References: <5AC4B64A-4286-11D9-8639-000393ACC76E@mac.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=UTF-8 Content-Transfer-Encoding: 8BIT To: unlisted-recipients:; (no To-header on input) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 998 Lines: 30 >Even timer interrupts are incredibly unpredictable. Instructions can >take >variable times to complete, and all instructions plus some indeterminate >cache operations and queue flushing must occur before the CPU can >even begin to service an interrupt. Well, don't timer interrupts happen every 1/1000 s (unless, of course, cli() is in effect)? >Also of note, there are small >critical >sections with interrupts disabled scattered all over the kernel and >scheduler, >in addition to varying memory latencies, etc. (NOTE: I am not an arch >expert In case you mean the RDTSC, it is of course better than the I8042, for random-aphy. Jan Engelhardt -- Gesellschaft für Wissenschaftliche Datenverarbeitung Am Fassberg, 37077 Göttingen, www.gwdg.de - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/