Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754364AbdGUPRu convert rfc822-to-8bit (ORCPT ); Fri, 21 Jul 2017 11:17:50 -0400 Received: from mail.eperm.de ([89.247.134.16]:60786 "EHLO mail.eperm.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751748AbdGUPRI (ORCPT ); Fri, 21 Jul 2017 11:17:08 -0400 From: Stephan =?ISO-8859-1?Q?M=FCller?= To: Arnd Bergmann Cc: "Theodore Ts'o" , Greg Kroah-Hartman , "Jason A. Donenfeld" , linux-crypto@vger.kernel.org, Linux Kernel Mailing List Subject: Re: [RFC PATCH v12 3/4] Linux Random Number Generator Date: Fri, 21 Jul 2017 17:17:05 +0200 Message-ID: <4074127.U4nTXhg6YI@tauon.chronox.de> In-Reply-To: References: <3910055.ntkqcq1Chb@positron.chronox.de> <2787001.lEj6P09Sfm@tauon.chronox.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset="iso-8859-1" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1265 Lines: 37 Am Freitag, 21. Juli 2017, 17:09:11 CEST schrieb Arnd Bergmann: Hi Arnd, > On Fri, Jul 21, 2017 at 10:57 AM, Stephan M?ller wrote: > > Am Freitag, 21. Juli 2017, 05:08:47 CEST schrieb Theodore Ts'o: > >> Um, the timer is the largest number of interrupts on my system. Compare: > >> CPU0 CPU1 CPU2 CPU3 > >> > >> LOC: 6396552 6038865 6558646 6057102 Local timer > >> interrupts > >> > >> with the number of disk related interrupts: > >> 120: 21492 139284 40513 1705886 PCI-MSI 376832-edge > >> > >> ahci[0000:00:17.0] > > > > They seem to be not picked up with the add_interrupt_randomness function. > > On x86, the local APIC timer has some special handling in > arch/x86/entry/entry_64.S that does not go through handle_irq_event(). > > I would assume that this is different when you boot with the "noapictimer" > option and use the hpet clockevent instead. > > On other architectures, the timer interrupt is often handled as a regular > IRQ as well. Thank you for the hint. Yet, I would think that timer interrupts can be identified by add_interrupt_randomness, either by the IRQ or the stuck test that was is suggested with the LRNG patch set. Ciao Stephan