From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:38556 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966918AbdEWOqv (ORCPT ); Tue, 23 May 2017 10:46:51 -0400 Subject: Patch "cpuidle: check dev before usage in cpuidle_use_deepest_state()" has been added to the 4.11-stable tree To: fei.li@intel.com, andriy.shevchenko@linux.intel.com, fengx.shi@intel.com, gregkh@linuxfoundation.org, rafael.j.wysocki@intel.com Cc: , From: Date: Tue, 23 May 2017 16:45:44 +0200 Message-ID: <149555074414964@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled cpuidle: check dev before usage in cpuidle_use_deepest_state() to the 4.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: cpuidle-check-dev-before-usage-in-cpuidle_use_deepest_state.patch and it can be found in the queue-4.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 41dc750ea67f317c0deedde713d1728425524ef2 Mon Sep 17 00:00:00 2001 From: "Li, Fei" Date: Thu, 27 Apr 2017 01:47:25 +0000 Subject: cpuidle: check dev before usage in cpuidle_use_deepest_state() From: Li, Fei commit 41dc750ea67f317c0deedde713d1728425524ef2 upstream. In case of there is no cpuidle devices registered, dev will be null, and panic will be triggered like below; In this patch, add checking of dev before usage, like that done in cpuidle_idle_call. Panic without fix: [ 184.961328] BUG: unable to handle kernel NULL pointer dereference at (null) [ 184.961328] IP: cpuidle_use_deepest_state+0x30/0x60 ... [ 184.961328] play_idle+0x8d/0x210 [ 184.961328] ? __schedule+0x359/0x8e0 [ 184.961328] ? _raw_spin_unlock_irqrestore+0x28/0x50 [ 184.961328] ? kthread_queue_delayed_work+0x41/0x80 [ 184.961328] clamp_idle_injection_func+0x64/0x1e0 Fixes: bb8313b603eb8 (cpuidle: Allow enforcing deepest idle state selection) Signed-off-by: Li, Fei Tested-by: Shi, Feng Reviewed-by: Andy Shevchenko Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/cpuidle/cpuidle.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -111,7 +111,8 @@ void cpuidle_use_deepest_state(bool enab preempt_disable(); dev = cpuidle_get_device(); - dev->use_deepest_state = enable; + if (dev) + dev->use_deepest_state = enable; preempt_enable(); } Patches currently in stable-queue which might be from fei.li@intel.com are queue-4.11/cpuidle-check-dev-before-usage-in-cpuidle_use_deepest_state.patch