From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751555AbdJVKnf (ORCPT ); Sun, 22 Oct 2017 06:43:35 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:44646 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751417AbdJVKne (ORCPT ); Sun, 22 Oct 2017 06:43:34 -0400 Date: Sun, 22 Oct 2017 12:43:27 +0200 (CEST) From: Thomas Gleixner To: Linus Torvalds cc: LKML , Ingo Molnar , "H. Peter Anvin" Subject: [GIT pull] smp/hotplug fix for 4.14 Message-ID: User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Linus, please pull the latest smp-urgent-for-linus git tree from: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git smp-urgent-for-linus The recent rework of the callback invocation missed to cleanup the leftovers of the operation, so under certain circumstances a subsequent CPU hotplug operation accesses stale data and crashes. Clean it up. Thanks, tglx ------------------> Thomas Gleixner (1): cpu/hotplug: Reset node state after operation kernel/cpu.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/cpu.c b/kernel/cpu.c index d851df22f5c5..04892a82f6ac 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -632,6 +632,11 @@ cpuhp_invoke_ap_callback(int cpu, enum cpuhp_state state, bool bringup, __cpuhp_kick_ap(st); } + /* + * Clean up the leftovers so the next hotplug operation wont use stale + * data. + */ + st->node = st->last = NULL; return ret; }