From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Fenghua Yu" Subject: [PATCH 0/2] Quiet power limit notification Date: Wed, 15 May 2013 06:36:55 -0700 Message-ID: <1368625017-6835-1-git-send-email-fenghua.yu@intel.com> Return-path: Received: from mga03.intel.com ([143.182.124.21]:58326 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932193Ab3EOUoE (ORCPT ); Wed, 15 May 2013 16:44:04 -0400 Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Rafael Wysocki , Len Brown Cc: linux-kernel , x86 , linux-pm , Fenghua Yu From: Fenghua Yu Power Limit Notification (X86_FEATURE_PLN) was added in Sandy Bridge to give the OS the option of knowing when the package has reached a configured power threshold. Linux-2.6.36 enabled this feature: 0199114c31798af5b83841b21759b64171060d9b (x86, hwmon: Package Level Thermal/Power: power limit) It enabld the interrupt, and the interrupt hander added to the MCE log and printed to the console: printk(KERN_CRIT "CPU%d: %s power limit notification (total events = %lu) printk(KERN_INFO "CPU%d: %s power limit normal\n" However, these events are quite routine on some systems under some conditions, alarming customers and provoking un-necessary customer support calls. So the MCE log entry was deleted in Linux-3.3: 29e9bf1841e4f9df13b4992a716fece7087dd237 (x86, mce, therm_throt: Don't report power limit and package level thermal throttle events in mcelog) Here we delete the corresponding kernel console messages, and then we disable the interrupt by default -- allowing it to be enabled by cmdline for diagnosis purposes. https://bugzilla.kernel.org/show_bug.cgi?id=36182 This pair of patches applies cleanly back to Linux-3.3.