From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754012AbcLLRun (ORCPT ); Mon, 12 Dec 2016 12:50:43 -0500 Received: from mail-yw0-f196.google.com ([209.85.161.196]:33638 "EHLO mail-yw0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753781AbcLLRul (ORCPT ); Mon, 12 Dec 2016 12:50:41 -0500 Date: Mon, 12 Dec 2016 12:50:39 -0500 From: Tejun Heo To: Vladimir Zapolskiy Cc: Greg Kroah-Hartman , Rob Herring , linux-kernel@vger.kernel.org Subject: Re: [PATCH] driver core: flush async calls before testing driver removal Message-ID: <20161212175039.GC13864@htj.duckdns.org> References: <20161210001519.24870-1-vz@mleia.com> <20161210073245.GA19610@kroah.com> <4c1eb9e4-3e49-660a-e3c2-d048d3189a26@mleia.com> <20161210130404.GB8145@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.7.1 (2016-10-04) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Sun, Dec 11, 2016 at 03:44:36AM +0200, Vladimir Zapolskiy wrote: > On 12/10/2016 03:04 PM, Greg Kroah-Hartman wrote: > > Hm, how does this not also get hit if you unbind/bind/unbind/bind/etc. > > from userspace as well? I don't think this is a > > CONFIG_DEBUG_TEST_DRIVER_REMOVE issue, but just that this option finds > > the problem corner cases as you are finding out :) > > > > and you are right, I managed to reproduce exactly the same race as before > running the unmodified kernel built from Torvald's branch head: Ah, you're right, so this means we need to add flush to all async probing drivers. Will do so for libata shortly. Thanks! -- tejun