Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759280AbcCDJ2K (ORCPT ); Fri, 4 Mar 2016 04:28:10 -0500 Received: from mx2.suse.de ([195.135.220.15]:59807 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759001AbcCDJDY (ORCPT ); Fri, 4 Mar 2016 04:03:24 -0500 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Xunlei Pang , Peter Zijlstra , Linus Torvalds , Mike Galbraith , Steven Rostedt , Thomas Gleixner , Ingo Molnar , Jiri Slaby Subject: [PATCH 3.12 064/116] sched/core: Clear the root_domain cpumasks in init_rootdomain() Date: Fri, 4 Mar 2016 10:01:49 +0100 Message-Id: X-Mailer: git-send-email 2.7.2 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2119 Lines: 59 From: Xunlei Pang 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 8295c69925ad53ec32ca54ac9fc194ff21bc40e2 upstream. root_domain::rto_mask allocated through alloc_cpumask_var() contains garbage data, this may cause problems. For instance, When doing pull_rt_task(), it may do useless iterations if rto_mask retains some extra garbage bits. Worse still, this violates the isolated domain rule for clustered scheduling using cpuset, because the tasks(with all the cpus allowed) belongs to one root domain can be pulled away into another root domain. The patch cleans the garbage by using zalloc_cpumask_var() instead of alloc_cpumask_var() for root_domain::rto_mask allocation, thereby addressing the issues. Do the same thing for root_domain's other cpumask memembers: dlo_mask, span, and online. Signed-off-by: Xunlei Pang Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1449057179-29321-1-git-send-email-xlpang@redhat.com Signed-off-by: Ingo Molnar Signed-off-by: Jiri Slaby --- kernel/sched/core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 9b2394fffc2f..e7de9175e586 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5054,11 +5054,11 @@ static int init_rootdomain(struct root_domain *rd) { memset(rd, 0, sizeof(*rd)); - if (!alloc_cpumask_var(&rd->span, GFP_KERNEL)) + if (!zalloc_cpumask_var(&rd->span, GFP_KERNEL)) goto out; - if (!alloc_cpumask_var(&rd->online, GFP_KERNEL)) + if (!zalloc_cpumask_var(&rd->online, GFP_KERNEL)) goto free_span; - if (!alloc_cpumask_var(&rd->rto_mask, GFP_KERNEL)) + if (!zalloc_cpumask_var(&rd->rto_mask, GFP_KERNEL)) goto free_online; if (cpupri_init(&rd->cpupri) != 0) -- 2.7.2