From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758869AbeD0Tee (ORCPT ); Fri, 27 Apr 2018 15:34:34 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:58808 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757590AbeD0Ted (ORCPT ); Fri, 27 Apr 2018 15:34:33 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 5B512600C9 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=okaya@codeaurora.org Subject: Re: pciehp 0000:00:1c.0:pcie004: Timeout on hotplug command 0x1038 (issued 65284 msec ago) To: Bjorn Helgaas , Paul Menzel Cc: Bjorn Helgaas , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Lukas Wunner References: <8770820b-85a0-172b-7230-3a44524e6c9f@molgen.mpg.de> <20180427192207.GG8199@bhelgaas-glaptop.roam.corp.google.com> From: Sinan Kaya Message-ID: Date: Fri, 27 Apr 2018 15:34:30 -0400 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20180427192207.GG8199@bhelgaas-glaptop.roam.corp.google.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Bjorn, Thanks for adding me. On 4/27/2018 3:22 PM, Bjorn Helgaas wrote: > Sinan mooted the idea of using a "no-wait" path of sending the "don't > generate hotplug interrupts" command. I think we should work on this > idea a little more. If we're shutting down the whole system, I can't > believe there's much value in *anything* we do in the pciehp_remove() > path. > > Maybe we should just get rid of pciehp_remove() (and probably > pcie_port_remove_service() and the other service driver remove methods) > completely. That dates from when the service drivers could be modules that > could be potentially unloaded, but unloading them hasn't been possible for > years. Shutdown path is also used for kexec. Leaving hotplug interrupts pending is dangerous for the newly loaded kernel as it leaves spurious interrupts during the new kernel boot. I think we should always disable the hotplug interrupt on shutdown. We might think of not waiting for command-completion as a middle-ground or go to polling path instead of interrupts all the time. Sinan -- Sinan Kaya Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.