From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7B432C43441 for ; Fri, 9 Nov 2018 00:29:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BF0CD2081D for ; Fri, 9 Nov 2018 00:29:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BF0CD2081D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lge.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727403AbeKIKHu (ORCPT ); Fri, 9 Nov 2018 05:07:50 -0500 Received: from lgeamrelo13.lge.com ([156.147.23.53]:36600 "EHLO lgeamrelo11.lge.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726915AbeKIKHu (ORCPT ); Fri, 9 Nov 2018 05:07:50 -0500 Received: from unknown (HELO lgemrelse6q.lge.com) (156.147.1.121) by 156.147.23.53 with ESMTP; 9 Nov 2018 09:29:42 +0900 X-Original-SENDERIP: 156.147.1.121 X-Original-MAILFROM: chanho.min@lge.com Received: from unknown (HELO WMRRD11NA101CK) (10.178.32.163) by 156.147.1.121 with ESMTP; 9 Nov 2018 09:29:42 +0900 X-Original-SENDERIP: 10.178.32.163 X-Original-MAILFROM: chanho.min@lge.com From: "Chanho Min" To: "'Oleg Nesterov'" Cc: "'Rafael J. Wysocki'" , "'Pavel Machek'" , "'Len Brown'" , "'Andrew Morton'" , "'Eric W. Biederman'" , "'Christian Brauner'" , "'Anna-Maria Gleixner'" , , , "'Seungho Park'" , "'Jongsung Kim'" , "'Inkyu Hwang'" , "'donghwan.jung'" References: <1541671796-8725-1-git-send-email-chanho.min@lge.com> <20181108105030.GB9939@redhat.com> In-Reply-To: <20181108105030.GB9939@redhat.com> Subject: RE: [PATCH] freezer: fix freeze timeout on exec Date: Fri, 9 Nov 2018 09:29:42 +0900 Message-ID: <02ce01d477c3$4ebec440$ec3c4cc0$@lge.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 15.0 Thread-Index: AQDMxpYjKJ+WuoJrEZbXJl5GJ1YyTAISrvFpp0VR2WA= Content-Language: ko Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > > > To fix this, I suggest a patch by emboding the mentioned solution. > > First, revive and rework cancel_freezing_and_thaw() function whitch > > stops the task from sleeping in refrigirator reliably. And, The task > > to be killed does not allow to freeze. > > Can't we simply change de_thread() to use freezable_schedule() ? > > Oleg. We need to change freezable_schedule_timeout() instead. freezable_schedule also can't be frozen if sub-threads can't stop schedule(). Furthermore, I'm not sure if it is safe to freeze it at de_thread(). diff --git a/fs/exec.c b/fs/exec.c index 9c5ee2a..291cbd6 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -942,7 +942,7 @@ static int de_thread(struct task_struct *tsk) while (sig->notify_count) { __set_current_state(TASK_KILLABLE); spin_unlock_irq(lock); - schedule(); + while (!freezable_schedule_timeout(HZ)); if (unlikely(__fatal_signal_pending(tsk))) goto killed; spin_lock_irq(lock); Chanho