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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 10C47C433E0 for ; Sun, 24 May 2020 15:38:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CDB5D207CB for ; Sun, 24 May 2020 15:38:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590334737; bh=FoydNPDHm8qaVR+FtRDqDSa8qSbQgfYOf6vh0Y6IBhE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=JQxJ8aLcE8krexKsLJADOmoV+fYzs61PpjIcVjV/sVOy5+FRky9lYUWuNcHFl2Qyz YOJIs1CXYn0lT73kQhGi3rNrT8817B/+d7rB+QIsAFLTU3G9+IHfqjId77XQGA08nf U7pRUoaSJ2Q4/K3nmV/lWDuFBjpKa+/ZP913F0rA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727798AbgEXPi5 (ORCPT ); Sun, 24 May 2020 11:38:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:39076 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726506AbgEXPi4 (ORCPT ); Sun, 24 May 2020 11:38:56 -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 DC85520787; Sun, 24 May 2020 15:38:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590334736; bh=FoydNPDHm8qaVR+FtRDqDSa8qSbQgfYOf6vh0Y6IBhE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=QgprcXwq0iv1tzjJUWjhCXd6iSnF9cnQDHiKse1W9RzCLswUJusFGLIH3P0i09s/e C6Ke/WCLnee74Ee/27UQUAeZnvSc0pAmCgw6vjsQgdMFWmh+C0Y4F2vW9oiFyUF7Wz 1xt8FMe4AgQVYiqL2Ib6ykX+KlRhtRAugDFkTY4U= Date: Sun, 24 May 2020 17:38:54 +0200 From: Greg KH To: Linus Torvalds Cc: Heikki Krogerus , Andrew Morton , Linux Kernel Mailing List , Stephen Rothwell Subject: Re: [GIT PULL] Driver core fixes for 5.7-rc7 - take 2 Message-ID: <20200524153854.GA5120@kroah.com> References: <20200523131759.GA55886@kroah.com> <20200523152922.GA224858@kroah.com> <20200524150018.GB11262@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200524150018.GB11262@kroah.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, May 24, 2020 at 05:00:18PM +0200, Greg KH wrote: > On Sat, May 23, 2020 at 11:14:28AM -0700, Linus Torvalds wrote: > > On Sat, May 23, 2020 at 8:29 AM Greg KH wrote: > > > > > > The kobject patch that was originally in here has now been reverted, as > > > Guenter reported boot problems with it on some of his systems. > > > > Hmm. That original patch looks obviously buggy: in kobject_cleanup() > > it would end up doing "kobject_put(parent)" regardless of whether it > > had actually done __kobject_del() or not. > > > > That _could_ have been intentional, but considering the commit > > message, it clearly wasn't in this case. It might be worth re-trying > > to the commit, just with that fixed. > > Turns out that wasn't the real problem here, the culprit is the > lib/test_printf.c code trying to tear down a kobject tree from the > parent down to the children (i.e. in the backwards order). The fix for this is now posted here: https://lore.kernel.org/lkml/20200524153041.2361-1-gregkh@linuxfoundation.org/ along with a kobject change to emit the remove uevent when the object is removed from sysfs (and still has a valid parent pointer), and not some unspecified time in the future. Let's see if people find this a better solution, and if so, I'll send it to you later in the week. thanks, greg k-h