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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 4E78CC73C50 for ; Tue, 9 Jul 2019 14:22:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2863C2080C for ; Tue, 9 Jul 2019 14:22:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562682133; bh=+0n8GlrqRKQUG/47XYRXFYBt5IHcvkFJ8wpGkEzqjUE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=q+JZG29BEbMVIvqWyUPAaSudnoiWJW2kwep+iMupx6RDTwsOI43qoJuC7/908wbbM paVd9ioOwdEzasDkKET+TH+nhXKqvNXr5RmCrwFtzR9bWBj4m8+qpGnlQN6lv8UMD7 GFfP9byOThYRKfglVp1DENW94r7lMnfyYzslZPAo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726765AbfGIOWL (ORCPT ); Tue, 9 Jul 2019 10:22:11 -0400 Received: from mail-qt1-f174.google.com ([209.85.160.174]:46378 "EHLO mail-qt1-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726374AbfGIOWL (ORCPT ); Tue, 9 Jul 2019 10:22:11 -0400 Received: by mail-qt1-f174.google.com with SMTP id h21so19582185qtn.13 for ; Tue, 09 Jul 2019 07:22:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=ZOJuPULlrE2vBj/9c6KgmQ77330wz9gdrf5HX3f8siY=; b=JDFVm5GfySg8Sd4dZ3vDpuc/MVCMu8c1Ktmjz2sipL5/bYCXthqdqTfl0bNqoCBCI1 dC7Dtu4MtLf2FqM7JRoqn0A/nQvL6M8evor8AgzJK/w1CufgGmOorzJZHxvCCl9aHaBd 4wDo7PBrRPXRTNWy4BIhCqgjQ8DqP39asU5NJ1ICrNyqUtBSlfDdcsa3VmeMvjtsIYMx /K3MgQfRw9h/p4QB2k7JpAgjFcsjru4n8+zEKkoILGXOc9kVEIKqfX91oNercxLdtLa/ ay7BjWlyoaz8EGyUH1HyGJgey/unBEiisACqinSU5ZD8z+5t/cdODiPdGMSk6sQqIZhB x1Ug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=ZOJuPULlrE2vBj/9c6KgmQ77330wz9gdrf5HX3f8siY=; b=nqmoBQqUPWIWLmX62UU6AHExF4bksz0LhxmqaiZI/tATDmsknjP1lpmA64hN8Aq/ID V1AQh/s/8aAkc9YObaXZ8J6AsvHnNucQCZqP1uqbaGntH4gX8aBVSfN7hvyVl9m0/MPh NS4mD/Rqsco86FrpQEH4kZ+rWycNbA6D80/1iIXSKS6BGCp/7LeyhQ+MPvpYiEooolWb zJPgSt2g6z7Uy0L8hpCkJDRS0bAhbQ/gvYGrnHrnhPvb17jl/9XVyU59UJrqBx+7VsER Cqog3QMP+4amnZ5H09U/Fob8Yh2NLi+5MRBSdrDCuBXr17aOJve3CK2TK1x2YC43K7VT K/0w== X-Gm-Message-State: APjAAAV0Fj2gC4iVfbUN3dEWaK81k/xeelcz0IZIg3DcwP+uQhMCKKxF xj/PwUQjHKok8N6cVLjUud8= X-Google-Smtp-Source: APXvYqxhZ6GaC0CzKYNXaWrldMUxDF2XzrreMcfaj5I6XaPJLQ6R+7EpiOkA1wtD/Y1dkMTF1J3YhQ== X-Received: by 2002:a0c:e1cd:: with SMTP id v13mr18273199qvl.245.1562682130349; Tue, 09 Jul 2019 07:22:10 -0700 (PDT) Received: from localhost ([2620:10d:c091:500::2:fa50]) by smtp.gmail.com with ESMTPSA id p4sm9672337qkb.84.2019.07.09.07.22.08 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 09 Jul 2019 07:22:08 -0700 (PDT) Date: Tue, 9 Jul 2019 07:22:06 -0700 From: Tejun Heo To: Hillf Danton Cc: syzbot , "gregkh@linuxfoundation.org" , "linux-kernel@vger.kernel.org" , "syzkaller-bugs@googlegroups.com" Subject: Re: WARNING in kernfs_create_dir_ns Message-ID: <20190709142206.GI657710@devbig004.ftw2.facebook.com> References: <20190709022335.12928-1-hdanton@sina.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190709022335.12928-1-hdanton@sina.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 09, 2019 at 10:23:35AM +0800, Hillf Danton wrote: > > I don't think this is the correct fix. It's being called with kobj > > whose parent's sysfs node is dangling. It gotta be fixed from the > > caller side. > > > Make sense? > > --- a/lib/kobject.c > +++ b/lib/kobject.c No, I meant that the problem likely is in the driver which is calling into the generic layer with a dead parent. We shouldn't be working around that from generic layer. Thanks. -- tejun