From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752720AbeBKJX4 (ORCPT ); Sun, 11 Feb 2018 04:23:56 -0500 Received: from mailout2.hostsharing.net ([83.223.90.233]:47133 "EHLO mailout2.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752273AbeBKJXy (ORCPT ); Sun, 11 Feb 2018 04:23:54 -0500 Date: Sun, 11 Feb 2018 10:25:25 +0100 From: Lukas Wunner To: Bjorn Helgaas Cc: linux-pci@vger.kernel.org, Prarit Bhargava , linux-kernel@vger.kernel.org, MUNEDA Takahiro , Kenji Kaneshige Subject: Re: [PATCH] PCI/portdrv: Remove "pcie_hp=nomsi" kernel parameter Message-ID: <20180211092525.GA1085@wunner.de> References: <20180211024815.73781.92853.stgit@bhelgaas-glaptop.roam.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180211024815.73781.92853.stgit@bhelgaas-glaptop.roam.corp.google.com> User-Agent: Mutt/1.6.1 (2016-04-27) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Feb 10, 2018 at 08:48:15PM -0600, Bjorn Helgaas wrote: > 7570a333d8b0 ("PCI: Add pcie_hp=nomsi to disable MSI/MSI-X for pciehp > driver") added the "pcie_hp=nomsi" kernel parameter to work around this > error on shutdown: > > irq 16: nobody cared (try booting with the "irqpoll" option) > Pid: 1081, comm: reboot Not tainted 3.2.0 #1 > ... > Disabling IRQ #16 > > This happened on an unspecified system (possibly involving the Integrated > Device Technology, Inc. Device 807f bridge). There is no automated way to > set this parameter, so it's not very useful for distributions or end users. > > I suspect the root cause of the underlying "irq 16: nobody cared" issue was > fixed by Prarit Bhargava with fda78d7a0ead ("PCI/MSI: > Stop disabling MSI/MSI-X in pci_device_shutdown()") and we probably don't > need "pcie_hp=nomsi" any more. > > Revert 7570a333d8b0 to remove the "pcie_hp=nomsi" parameter. This has been useful when bringing up broken hardware which claims to support MSI but really doesn't, such as in commit 19bf4d4f909d ("thunderbolt: Support 1st gen Light Ridge controller"). In this case I didn't know why the controller wasn't sending interrupts, on a hunch I tried "pcie_hp=nomsi" and that worked, and looking in the macOS source code I was able to verify that they disable MSI for this particular hardware as well. So please leave it in to ease developers' lives. Thanks, Lukas