From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754039AbcKUKgg (ORCPT ); Mon, 21 Nov 2016 05:36:36 -0500 Received: from terminus.zytor.com ([198.137.202.10]:59216 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752452AbcKUKgf (ORCPT ); Mon, 21 Nov 2016 05:36:35 -0500 Date: Mon, 21 Nov 2016 02:35:59 -0800 From: tip-bot for Borislav Petkov Message-ID: Cc: Yazen.Ghannam@amd.com, peterz@infradead.org, linux-kernel@vger.kernel.org, mingo@kernel.org, bigeasy@linutronix.de, bp@suse.de, tglx@linutronix.de, torvalds@linux-foundation.org, hpa@zytor.com Reply-To: linux-kernel@vger.kernel.org, peterz@infradead.org, Yazen.Ghannam@amd.com, mingo@kernel.org, bp@suse.de, bigeasy@linutronix.de, hpa@zytor.com, torvalds@linux-foundation.org, tglx@linutronix.de In-Reply-To: <20161119103402.5227-1-bp@alien8.de> References: <20161119103402.5227-1-bp@alien8.de> To: linux-tip-commits@vger.kernel.org Subject: [tip:smp/hotplug] x86/MCE/AMD: Fix thinko about thresholding_en Git-Commit-ID: 254fe9c7a4187ebf5ce23e0ca0e9ba98b1dbef18 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 254fe9c7a4187ebf5ce23e0ca0e9ba98b1dbef18 Gitweb: http://git.kernel.org/tip/254fe9c7a4187ebf5ce23e0ca0e9ba98b1dbef18 Author: Borislav Petkov AuthorDate: Sat, 19 Nov 2016 11:34:02 +0100 Committer: Ingo Molnar CommitDate: Mon, 21 Nov 2016 11:02:12 +0100 x86/MCE/AMD: Fix thinko about thresholding_en So adding thresholding_en et al was a good thing for removing the per-CPU thresholding callback, i.e., threshold_cpu_callback. But, in order for it to work and especially that test in mce_threshold_create_device() so that all thresholding banks get properly created and not the whole thing to fail with a NULL ptr dereference at mce_cpu_pre_down() when we offline the CPUs, we need to set the thresholding_en flag *before* we start creating the devices. Yap, it failed because thresholding_en wasn't set at the time we were creating the banks so we didn't create any and then at mce_cpu_pre_down() -> mce_threshold_remove_device() time, we would blow up. And the fix is actually easy: we have thresholding on the system when we have managed to set the thresholding vector to amd_threshold_interrupt() earlier in mce_amd_feature_init() while we were picking apart the thresholding banks and what is set and what not. So let's do that. Signed-off-by: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Sebastian Andrzej Siewior Cc: Thomas Gleixner Cc: Yazen Ghannam Fixes: 4d7b02d58c40 ("x86/mcheck: Split threshold_cpu_callback into two callbacks") Link: http://lkml.kernel.org/r/20161119103402.5227-1-bp@alien8.de Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/mcheck/mce_amd.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c index c33a3ee..4e82e53 100644 --- a/arch/x86/kernel/cpu/mcheck/mce_amd.c +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c @@ -1134,6 +1134,9 @@ static __init int threshold_init_device(void) { unsigned lcpu = 0; + if (mce_threshold_vector == amd_threshold_interrupt) + thresholding_en = true; + /* to hit CPUs online before the notifier is up */ for_each_online_cpu(lcpu) { int err = mce_threshold_create_device(lcpu); @@ -1142,8 +1145,6 @@ static __init int threshold_init_device(void) return err; } - thresholding_en = true; - return 0; } /*