From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759088Ab2DYL6l (ORCPT ); Wed, 25 Apr 2012 07:58:41 -0400 Received: from mga02.intel.com ([134.134.136.20]:30766 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757111Ab2DYL6k (ORCPT ); Wed, 25 Apr 2012 07:58:40 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,352,1309762800"; d="scan'208";a="133618057" Subject: [PATCH] sched: fix OOPS when build_sched_domains percpu allocation fails From: "he, bo" To: akpm@linux-foundation.org, mingo@elte.hu, a.p.zijlstra@chello.nl, rusty@rustcorp.com.au, william.douglas@intel.com, linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, yanmin_zhang@linux.intel.com Cc: yanmin.zhang@intel.com, bo.he@intel.com Content-Type: text/plain; charset="UTF-8" Date: Wed, 25 Apr 2012 19:59:21 +0800 Message-ID: <1335355161.5892.17.camel@hebo> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "he, bo" Under extreme memory used up situation, percpu allocation might fails. We hit it when system go to suspend-to-ram. EIP: [] build_sched_domains+0x23a/0xad0 SS:ESP 0068:de725d04 CR2: 0000000034811000 ---[ end trace d6086359b670b975 ]--- Kernel panic - not syncing: Fatal exception Pid: 3026, comm: kworker/u:3 Tainted: G D W 3.0.8-137473-gf42fbef #1 Call Trace: [] panic+0x66/0x16c [] ? oops_exit+0x61/0x90 [] oops_end+0xb9/0xd0 [] no_context+0xc6/0x1f0 [] __bad_area_nosemaphore+0x98/0x140 [] ? dump_trace+0x7f/0xf0 [] ? pgtable_bad+0x130/0x130 [] bad_area_nosemaphore+0x17/0x20 [] do_page_fault+0x270/0x3c0 [] ? pcpu_alloc+0x12ca/0x1300 [] ? pgtable_bad+0x130/0x130 [] ? pgtable_bad+0x130/0x130 [] error_code+0x5f/0x64 [] ? shmem_setattr+0x198/0x230 [] ? pgtable_bad+0x130/0x130 [] ? build_sched_domains+0x23a/0xad0 [] ? _raw_spin_unlock_irqrestore+0x26/0x50 [] partition_sched_domains+0x287/0x4b0 [] cpuset_update_active_cpus+0x1fe/0x210 [] ? __cpufreq_remove_dev+0x167/0x360 [] ? down_write+0x1c/0x40 [] cpuset_cpu_inactive+0x1d/0x30 [] notifier_call_chain+0x52/0x90 [] __raw_notifier_call_chain+0x1e/0x30 [] _cpu_down+0x89/0x230 [] disable_nonboot_cpus+0x79/0x100 [] suspend_devices_and_enter+0x133/0x2e0 [] enter_state+0x11d/0x180 [] pm_suspend+0x27/0x70 [] suspend+0x96/0x1d0 [] process_one_work+0x103/0x400 [] ? power_suspend_late+0x90/0x90 [] worker_thread+0x12c/0x4b0 [] ? sub_preempt_count+0x3d/0x50 [] ? _raw_spin_unlock_irqrestore+0x26/0x50 [] ? manage_workers+0x520/0x520 [] kthread+0x74/0x80 [] ? __init_kthread_worker+0x30/0x30 [] kernel_thread_helper+0x6/0x10 Signed-off-by: he, bo Reviewed-by: Zhang, Yanmin --- kernel/sched/core.c | 22 ++++++++++++++++------ 1 files changed, 16 insertions(+), 6 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 4603b9d..0533a68 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6405,16 +6405,26 @@ static void __sdt_free(const struct cpumask *cpu_map) struct sd_data *sdd = &tl->data; for_each_cpu(j, cpu_map) { - struct sched_domain *sd = *per_cpu_ptr(sdd->sd, j); - if (sd && (sd->flags & SD_OVERLAP)) - free_sched_groups(sd->groups, 0); - kfree(*per_cpu_ptr(sdd->sd, j)); - kfree(*per_cpu_ptr(sdd->sg, j)); - kfree(*per_cpu_ptr(sdd->sgp, j)); + struct sched_domain *sd; + + if (sdd->sd) { + sd = *per_cpu_ptr(sdd->sd, j); + if (sd && (sd->flags & SD_OVERLAP)) + free_sched_groups(sd->groups, 0); + kfree(*per_cpu_ptr(sdd->sd, j)); + } + + if (sdd->sg) + kfree(*per_cpu_ptr(sdd->sg, j)); + if (sdd->sgp) + kfree(*per_cpu_ptr(sdd->sgp, j)); } free_percpu(sdd->sd); + sdd->sd = NULL; free_percpu(sdd->sg); + sdd->sg = NULL; free_percpu(sdd->sgp); + sdd->sgp = NULL; } } -- 1.7.6