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Wed, 14 Oct 2020 08:30:40 +0000 From: qiang.zhang@windriver.com To: tj@kernel.org, pmladek@suse.com, hdanton@sina.com Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH v4] kthread_worker: Prevent queuing delayed work from timer_fn when it is being canceled Date: Wed, 14 Oct 2020 16:30:30 +0800 Message-Id: <20201014083030.16895-1-qiang.zhang@windriver.com> X-Mailer: git-send-email 2.17.1 Content-Type: text/plain X-Originating-IP: [60.247.85.82] X-ClientProxiedBy: BY5PR03CA0012.namprd03.prod.outlook.com (2603:10b6:a03:1e0::22) To BYAPR11MB2632.namprd11.prod.outlook.com (2603:10b6:a02:c4::17) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from pek-qzhang2-d1.wrs.com (60.247.85.82) by BY5PR03CA0012.namprd03.prod.outlook.com (2603:10b6:a03:1e0::22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3477.21 via Frontend Transport; Wed, 14 Oct 2020 08:30:38 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 619fc318-c0c4-4220-3b3e-08d8701b6f2a X-MS-TrafficTypeDiagnostic: BYAPR11MB2679: X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:2331; 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kthread_delayed_work_timer_fn() kthread_insert_work(); BUG: kthread_insert_work() should not get called when work->canceling is set. Cc: Reviewed-by: Petr Mladek Acked-by: Tejun Heo Signed-off-by: Zqiang --- v1->v2->v3: Change the description of the problem and add 'Reviewed-by' tags. v3->v4: Add 'stable' and 'Acked-by' tags. kernel/kthread.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/kthread.c b/kernel/kthread.c index 3edaa380dc7b..85a2c9b32049 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -897,7 +897,8 @@ void kthread_delayed_work_timer_fn(struct timer_list *t) /* Move the work from worker->delayed_work_list. */ WARN_ON_ONCE(list_empty(&work->node)); list_del_init(&work->node); - kthread_insert_work(worker, work, &worker->work_list); + if (!work->canceling) + kthread_insert_work(worker, work, &worker->work_list); raw_spin_unlock_irqrestore(&worker->lock, flags); } -- 2.17.1