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=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 D9405C282C0 for ; Wed, 23 Jan 2019 19:10:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A85592184B for ; Wed, 23 Jan 2019 19:10:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726101AbfAWTKu (ORCPT ); Wed, 23 Jan 2019 14:10:50 -0500 Received: from mga12.intel.com ([192.55.52.136]:14135 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726365AbfAWTKr (ORCPT ); Wed, 23 Jan 2019 14:10:47 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 23 Jan 2019 11:10:46 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,512,1539673200"; d="scan'208";a="293825323" Received: from unknown (HELO localhost.localdomain) ([10.232.112.69]) by orsmga005.jf.intel.com with ESMTP; 23 Jan 2019 11:10:45 -0800 Date: Wed, 23 Jan 2019 12:09:46 -0700 From: Keith Busch To: Lukas Wunner Cc: Alex_Gagniuc@Dellteam.com, linux-pci@vger.kernel.org, bhelgaas@google.com, Austin.Bolen@dell.com Subject: Re: PCI: hotplug: Erroneous removal of hotplug PCI devices Message-ID: <20190123190945.GD6629@localhost.localdomain> References: <356432a0556d4da59f8ba5cf1d750019@ausx13mps317.AMER.DELL.COM> <20190123185420.2pennvzvkuhqfmtj@wunner.de> <20190123190723.rnt5llkek5st7ddt@wunner.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190123190723.rnt5llkek5st7ddt@wunner.de> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Jan 23, 2019 at 08:07:23PM +0100, Lukas Wunner wrote: > On Wed, Jan 23, 2019 at 07:54:20PM +0100, Lukas Wunner wrote: > > So I don't see a perfect solution. What device are we talking about > > anyway? 400 ms is a *long* time. > > Also, how exactly does this issue manifest itself: Is it just an > annoyance that the slot is brought up/down/up or does it not work > at all? Yeah, there is an nvme driver bug that hits a dead lock if you bring a very quick add-remove sequence. The nvme remove tries to delete IO resources before the async probe side set them up, so the driver doesn't actually see that they're invalid. I have a proposed fix, but waiting to here if it is successful. bz: https://bugzilla.kernel.org/show_bug.cgi?id=202081