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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 1BA74C6778A for ; Mon, 23 Jul 2018 00:38:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 15AC620858 for ; Mon, 23 Jul 2018 00:38:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 15AC620858 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.crashing.org 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 S1731170AbeGWBe0 (ORCPT ); Sun, 22 Jul 2018 21:34:26 -0400 Received: from gate.crashing.org ([63.228.1.57]:43639 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730664AbeGWBe0 (ORCPT ); Sun, 22 Jul 2018 21:34:26 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id w6N0ZhiM024651; Sun, 22 Jul 2018 19:35:44 -0500 Message-ID: <57c12574e0daf5f38dd8e871299b8dd4f41c5d53.camel@kernel.crashing.org> Subject: Re: [PATCH 1/2] drivers: core: Don't try to use a dead glue_dir From: Benjamin Herrenschmidt To: Greg Kroah-Hartman Cc: Linus Torvalds , "Eric W. Biederman" , Joel Stanley , Linux Kernel Mailing List Date: Mon, 23 Jul 2018 10:35:43 +1000 In-Reply-To: <20180721075350.GA17840@kroah.com> References: <828fb935c0cd04e74a09b8ed2b78aca405d7c5b2.camel@kernel.crashing.org> <20180707164838.GC16279@kroah.com> <20180721075350.GA17840@kroah.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.4 (3.28.4-1.fc28) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2018-07-21 at 09:53 +0200, Greg Kroah-Hartman wrote: > > > So I hate using kobject_get_unless_zero(), and resisted ever adding it > > > to the tree as it shows a bad locking/tree situation as you point out > > > here. But for some reason, the block developers seemed to insist they > > > needed it, and so it is in the tree for them. I don't want it to spread > > > if at all possible, which makes me want to reject this patch as this > > > should be "a case that can never be hit". > > > > Except it can in that situation... at least unless you get my patch 2/2 > > (or the newer one I'm about to send that avoids adding a child counter > > and uses the one in kernfs instead). > > To follow up on this. I've applied the 2/2 patch for this series, so > this 1/2 "should" not be needed. Ben, if you still see this trigger > with that, I guess I can take this, but it still feels wrong to me :) I've tested my repro-case with only patch 2 and it doesn't trigger anymore, as expected. That said, you and Linus might want to sync your clocks on how sysfs "should" work :-) Cheers, Ben.