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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 8F0ECC43381 for ; Wed, 20 Mar 2019 13:24:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5E86021850 for ; Wed, 20 Mar 2019 13:24:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726916AbfCTNYP (ORCPT ); Wed, 20 Mar 2019 09:24:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60292 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726303AbfCTNYP (ORCPT ); Wed, 20 Mar 2019 09:24:15 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 660E630842CF; Wed, 20 Mar 2019 13:24:15 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.43.17.34]) by smtp.corp.redhat.com (Postfix) with SMTP id E696517F8D; Wed, 20 Mar 2019 13:24:12 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Wed, 20 Mar 2019 14:24:14 +0100 (CET) Date: Wed, 20 Mar 2019 14:24:11 +0100 From: Oleg Nesterov To: Michal Hocko Cc: syzbot , chanho.min@lge.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, pavel@ucw.cz, rafael.j.wysocki@intel.com, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk Subject: Re: WARNING: syz-executor still has locks held! Message-ID: <20190320132410.GB21673@redhat.com> References: <0000000000000e4a41057b6c9792@google.com> <0000000000004cdec6058485b2ce@google.com> <20190320131655.GA8696@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190320131655.GA8696@dhcp22.suse.cz> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.40]); Wed, 20 Mar 2019 13:24:15 +0000 (UTC) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 03/20, Michal Hocko wrote: > > Yes we do hold the cgred mutex while calling freezable_schedule but why > are we getting a warning is not really clear to me. The task should be > hidden from the freezer so why do we warn at all? try_to_freeze() calls debug_check_no_locks_held() and this makes sense. Another task can sleep waiting for the same lock; in this case try_to_freeze_tasks() will fail but it won't blame the lock holder exactly because it is "hidden from the freezer". Oleg.