From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752211AbaGKCZI (ORCPT ); Thu, 10 Jul 2014 22:25:08 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33696 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751689AbaGKCZF (ORCPT ); Thu, 10 Jul 2014 22:25:05 -0400 Message-ID: <1405045492.26540.67.camel@deadeye.wl.decadent.org.uk> Subject: Interrupt randomness in 3.14.10-rt From: Ben Hutchings To: Thomas Gleixner Cc: LKML , stable-rt@vger.kernel.org Date: Fri, 11 Jul 2014 03:24:52 +0100 Content-Type: multipart/signed; micalg="pgp-sha512"; protocol="application/pgp-signature"; boundary="=-F6EKBV5rcERTzsdzPdLI" X-Mailer: Evolution 3.12.2-1 Mime-Version: 1.0 X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-F6EKBV5rcERTzsdzPdLI Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable I noticed this change between 3.14.3-rt5 and 3.14.10-rt7: --- debian/patches/features/all/rt/random-make-it-work-on-rt.patch (re= vision 21522) +++ debian/patches/features/all/rt/random-make-it-work-on-rt.patch (wo= rking copy) [...] ---- a/kernel/irq/manage.c -+++ b/kernel/irq/manage.c -@@ -942,6 +942,12 @@ static int irq_thread(void *data) - if (action_ret =3D=3D IRQ_HANDLED) - atomic_inc(&desc->threads_handled); -=20 -+#ifdef CONFIG_PREEMPT_RT_FULL -+ migrate_disable(); -+ add_interrupt_randomness(action->irq, 0, -+ desc->random_ip ^ (unsigned long) action); -+ migrate_enable(); -+#endif - wake_threads_waitq(desc); - } -=20 (I.e. old patch included these additions, new patch doesn't.) Evidently this was made in the announced 3.14.10-rt6, not -rt7. Was it intentional? Now irq_desc::random_ip is set but never used. Ben. --=20 Ben Hutchings To err is human; to really foul things up requires a computer. --=-F6EKBV5rcERTzsdzPdLI Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIVAwUAU79K+ee/yOyVhhEJAQqVcg/5AeF/OuMeK++33vI+MnUlrhuHbjuoDa3Q OF4VGVWda501pDb6JonjdYxlUttQV4LEWwv5rxKfU1tO7Da5W0lXpioqdyzKzk1H 9hkZZAlmhXOvjQf6pKwK6bIRDPOnQHWhbLIw3Xa3bLw35lNdVLZt0EJIQQtu1uvg z0gjLEB7TLoc4eCFPy51OQl19ovMwWpwRatW/tWh7sjhnr2o8DB+r9DWZBAcy/z4 iVPolozW5hobIh11uh8UyPWGQxjdSupyhcE4rqXQIDXB+7Pg5bkplXVI/PxoAP0Y u8kb83jCduZRK1ARTYtnJTog7vsyvhSh1pku2k2ocZj2XoIyS6YN+TUJRvqrXJZM 4chGS8CMumLR79bF+Hf0FapuDQkbydtroR1BPkNjmhJh9lgSOm9pfARZyIAimjJ2 KwxDdzhQcNHySzJKDUuModcy+nz+5SsrgmPRJGKPxE97TaUELWIjlrCt0fugSIXt OXxDJqkO5JRq43UjOyJ4D6Fv8/CQdF4V9wHPSBO0AURdXIgul4RZrg/ccVLeOMw4 cBLYu/c/J2jFx+Vz7B8MNLr4HyEwWcYUEB3XYPwhE4LP0rS95hS34VSbSkDHSv5E CYoCZitCQX0NFkBmOwXKCrLQbH1/PVOS7jBU7iknbkeS44PXwW+MH8+rtuMnEAOd Ol2vSlAJfyY= =7wtc -----END PGP SIGNATURE----- --=-F6EKBV5rcERTzsdzPdLI--