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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 F07F9C0650E for ; Thu, 4 Jul 2019 05:41:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C3F7621882 for ; Thu, 4 Jul 2019 05:41:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562218863; bh=e8TNcyelEwd3uBfOzE7u6HsVzn4zKxUqsTBHoLp6L4Y=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Nmk6rTlemCui3Q58QzlbGEH1AIn1YZaxkTgujAWs9WKBTFfu9M7FkGGU58M3w9dyV VCLbLXbDlBzbbHku1An3aH6ExtoYzaDexGAxpluSBzXntHXjL4L3RGHXmwnb8HINLK /o3QpDFeOu+0JjNV8BPiOuGMEP5Ok80Q7abdvTCI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727226AbfGDFlC (ORCPT ); Thu, 4 Jul 2019 01:41:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:47206 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725879AbfGDFlC (ORCPT ); Thu, 4 Jul 2019 01:41:02 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9560221882; Thu, 4 Jul 2019 05:41:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562218861; bh=e8TNcyelEwd3uBfOzE7u6HsVzn4zKxUqsTBHoLp6L4Y=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ku0Y7hpoqBS6APNaFuh3irUgN47JKJr78lnWKhlsZ/VI6RkaVk4gAxP9dRYX+4n5k a80+L+oQbzZGypfwGACLFiIEHBXubXt5nBmKXobQHaZTmIOG4ioBNK4mXYKmYotUcF 1Z9Mes4ZtNuHFHgEFGePG5+XzLuNJH0Wd/Ba2onk= Date: Thu, 4 Jul 2019 07:40:58 +0200 From: Greg KH To: Benjamin Herrenschmidt Cc: Muchun Song , rafael@kernel.org, prsood@codeaurora.org, mojha@codeaurora.org, gkohli@codeaurora.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 OPT2] driver core: Fix use-after-free and double free on glue directory Message-ID: <20190704054058.GC347@kroah.com> References: <20190626144021.7249-1-smuchun@gmail.com> <20190703193606.GA8452@kroah.com> <319ae04497cf1982076bf801cfdf565046096fd4.camel@kernel.crashing.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <319ae04497cf1982076bf801cfdf565046096fd4.camel@kernel.crashing.org> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 04, 2019 at 08:57:13AM +1000, Benjamin Herrenschmidt wrote: > On Wed, 2019-07-03 at 21:36 +0200, Greg KH wrote: > > > > > -static struct kobject *get_device_parent(struct device *dev, > > > - struct device *parent) > > > +/** > > > + * __get_device_parent() - Get the parent device kobject. > > > + * @dev: Pointer to the device structure. > > > + * @parent: Pointer to the parent device structure. > > > + * @lock: When we live in a glue directory, should we hold the > > > + * gdp_mutex lock when this function returns? If @lock > > > + * is true, this function returns with the gdp_mutex > > > + * holed. Otherwise it will not. > > > > Ugh, if you are trying to get me to hate one version of these patches, > > this is how you do it :) > > > > A function should not "sometimes takes a lock, sometimes does not, > > depending on a parameter passed into it" That way lies madness... > > Yes, I prefer this approach to the fix but I dont like the patch either > for the same reason... > > ... > > > Anyway, this is a mess. > > > > Ugh I hate glue dirs... > > Amen... Well, can we just remove them? Who relies on them anymore? thanks, greg k-h