Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760208Ab3GSL1M (ORCPT ); Fri, 19 Jul 2013 07:27:12 -0400 Received: from mail-wi0-f178.google.com ([209.85.212.178]:56064 "EHLO mail-wi0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751415Ab3GSL1I (ORCPT ); Fri, 19 Jul 2013 07:27:08 -0400 From: Julien Grall To: stefano.stabellini@eu.citrix.com Cc: ian.campbell@citrix.com, patches@linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, xen-devel@lists.xen.org, konrad.wilk@oracle.com, Julien Grall Subject: [PATCH v2] xen/arm: disable cpuidle and cpufreq when linux is running as dom0 Date: Fri, 19 Jul 2013 12:27:00 +0100 Message-Id: <1374233220-13770-1-git-send-email-julien.grall@linaro.org> X-Mailer: git-send-email 1.7.10.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1398 Lines: 50 When linux is running as dom0, Xen doesn't show the physical cpu but a virtual CPU. On some ARM SOC (for instance the exynos 5250), linux registers callbacks for cpuidle and cpufreq. When these callbacks are called, they will modify directly the physical cpu not the virtual one. It can impact the whole board instead of only dom0. Signed-off-by: Julien Grall --- Changes in v2: - Disable cpufreq --- arch/arm/xen/enlighten.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index 49839d8..af82792 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -24,6 +24,8 @@ #include #include #include +#include +#include #include @@ -292,6 +294,12 @@ static int __init xen_pm_init(void) { pm_power_off = xen_power_off; arm_pm_restart = xen_restart; + /* + * Making sure board specific code will not set up ops for + * cpu idle and cpu freq. + */ + disable_cpuidle(); + disable_cpufreq(); return 0; } -- 1.7.10.4 -- 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/