From patchwork Wed May 20 00:14:13 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 474096 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 5ECE7140077 for ; Wed, 20 May 2015 09:49:11 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751174AbbESXsy (ORCPT ); Tue, 19 May 2015 19:48:54 -0400 Received: from v094114.home.net.pl ([79.96.170.134]:58017 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1750750AbbESXsx (ORCPT ); Tue, 19 May 2015 19:48:53 -0400 Received: from aerh127.neoplus.adsl.tpnet.pl (79.191.189.127) (HELO vostro.rjw.lan) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer v0.80) id 3e21c11cc44f36be; Wed, 20 May 2015 01:48:51 +0200 From: "Rafael J. Wysocki" To: Bjorn Helgaas Cc: Linux PCI , Linux Kernel Mailing List , ACPI Devel Maling List , Mika Westerberg Subject: [PATCH] PCI / hotplug / ACPI: Check ignore_hotplug for all downstream devices Date: Wed, 20 May 2015 02:14:13 +0200 Message-ID: <1499297.p2drhZLZaT@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/4.0.0+; KDE/4.11.5; x86_64; ; ) MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Rafael J. Wysocki If the ignore_hotplug flag is set for a PCI device without an ACPI companion and a bus check notification is received for an ancestor bridge that is not the device's parent, ACPIPHP will ignore that flag. Namely, in that case acpiphp_check_bridge() is called for the target bridge and if all of the devices immediately below the bridge are still present, trim_stale_devices() will be called for each of them. That function recursively walks the hierarchy downwards and removes device objects corresponding to devices that don't appear to be present any more. Unfortunately, it only checks ignore_hotplug for devices having ACPI companions, so it will remove the others (if they don't respond) regardless of the ignore_hotplug value. Fix the problem by making trim_stale_devices() take ignore_hotplug into consideration regardless of whether or not an ACPI companion is present for the device it has been called for. Signed-off-by: Rafael J. Wysocki --- This may fix BZ61891, but even if it doesn't, the bug is quite obvious to me. Should be applicable since commit b440bde74f04 (PCI: Add pci_ignore_hotplug() to ignore hotplug events for a device) which shipped in 3.17. --- drivers/pci/hotplug/acpiphp_glue.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Index: linux-pm/drivers/pci/hotplug/acpiphp_glue.c =================================================================== --- linux-pm.orig/drivers/pci/hotplug/acpiphp_glue.c +++ linux-pm/drivers/pci/hotplug/acpiphp_glue.c @@ -632,15 +632,14 @@ static void trim_stale_devices(struct pc { struct acpi_device *adev = ACPI_COMPANION(&dev->dev); struct pci_bus *bus = dev->subordinate; - bool alive = false; + bool alive = dev->ignore_hotplug; if (adev) { acpi_status status; unsigned long long sta; status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta); - alive = (ACPI_SUCCESS(status) && device_status_valid(sta)) - || dev->ignore_hotplug; + alive = alive || (ACPI_SUCCESS(status) && device_status_valid(sta)); } if (!alive) alive = pci_device_is_present(dev);