Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752360AbeAAO0n (ORCPT + 1 other); Mon, 1 Jan 2018 09:26:43 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:41976 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752318AbeAAO0k (ORCPT ); Mon, 1 Jan 2018 09:26:40 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Thomas Gleixner , Maarten Lankhorst , "Rafael J. Wysocki" , Bjorn Helgaas Subject: [PATCH 4.4 08/63] PCI / PM: Force devices to D0 in pci_pm_thaw_noirq() Date: Mon, 1 Jan 2018 15:24:26 +0100 Message-Id: <20180101140043.866409981@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20180101140042.456380281@linuxfoundation.org> References: <20180101140042.456380281@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Rafael J. Wysocki commit 5839ee7389e893a31e4e3c9cf17b50d14103c902 upstream. It is incorrect to call pci_restore_state() for devices in low-power states (D1-D3), as that involves the restoration of MSI setup which requires MMIO to be operational and that is only the case in D0. However, pci_pm_thaw_noirq() may do that if the driver's "freeze" callbacks put the device into a low-power state, so fix it by making it force devices into D0 via pci_set_power_state() instead of trying to "update" their power state which is pointless. Fixes: e60514bd4485 (PCI/PM: Restore the status of PCI devices across hibernation) Reported-by: Thomas Gleixner Reported-by: Maarten Lankhorst Tested-by: Thomas Gleixner Tested-by: Maarten Lankhorst Signed-off-by: Rafael J. Wysocki Acked-by: Bjorn Helgaas Signed-off-by: Greg Kroah-Hartman --- drivers/pci/pci-driver.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -944,7 +944,12 @@ static int pci_pm_thaw_noirq(struct devi if (pci_has_legacy_pm_support(pci_dev)) return pci_legacy_resume_early(dev); - pci_update_current_state(pci_dev, PCI_D0); + /* + * pci_restore_state() requires the device to be in D0 (because of MSI + * restoration among other things), so force it into D0 in case the + * driver's "freeze" callbacks put it into a low-power state directly. + */ + pci_set_power_state(pci_dev, PCI_D0); pci_restore_state(pci_dev); if (drv && drv->pm && drv->pm->thaw_noirq)