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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 B823DC4167D for ; Thu, 9 Sep 2021 12:36:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D0C4611BF for ; Thu, 9 Sep 2021 12:36:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350341AbhIIMhK (ORCPT ); Thu, 9 Sep 2021 08:37:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:34714 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353755AbhIIMYs (ORCPT ); Thu, 9 Sep 2021 08:24:48 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 55A8461B01; Thu, 9 Sep 2021 11:51:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631188289; bh=cU9PSdYY4xYV77BMmc2t29QuzezwuZebPFAyRME90CA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tM3+tHcD67Uh0kaz7UI3cFhJ05CQrAP066drS0p7S4AJ2zGaAVG6tTf1UZLQPN8cU Pq+mCz1sozrJP9FAD9/7kNIBdqJKRSD1Le2vxxHQvU/SHK5DER4kKffydOMrw4ofSC iiI9VDYch+lMUw5v5MNlF00/DzsutFeCzZmfrKRG6DCOuasI3XYaXisTyRMdjQMKai cVd9T6x+xUw3yCxqau8mbIwVG8bPSjkU9g9H527D2Fdre6YfGDYaj/5EzDgbKkP9Gp FBgKWJz7JY91OxDPWZiH9FWbfUkPi7iClfs4Ftu8Cl4pumYSw8iVFy8NgRoH9Mzb6y 4HaNJ1cMb5THQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Rafael J. Wysocki" , Maximilian Luz , Sasha Levin , linux-pci@vger.kernel.org Subject: [PATCH AUTOSEL 5.10 008/176] PCI: Use pci_update_current_state() in pci_enable_device_flags() Date: Thu, 9 Sep 2021 07:48:30 -0400 Message-Id: <20210909115118.146181-8-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210909115118.146181-1-sashal@kernel.org> References: <20210909115118.146181-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: "Rafael J. Wysocki" [ Upstream commit 14858dcc3b3587f4bb5c48e130ee7d68fc2b0a29 ] Updating the current_state field of struct pci_dev the way it is done in pci_enable_device_flags() before calling do_pci_enable_device() may not work. For example, if the given PCI device depends on an ACPI power resource whose _STA method initially returns 0 ("off"), but the config space of the PCI device is accessible and the power state retrieved from the PCI_PM_CTRL register is D0, the current_state field in the struct pci_dev representing that device will get out of sync with the power.state of its ACPI companion object and that will lead to power management issues going forward. To avoid such issues, make pci_enable_device_flags() call pci_update_current_state() which takes ACPI device power management into account, if present, to retrieve the current power state of the device. Link: https://lore.kernel.org/lkml/20210314000439.3138941-1-luzmaximilian@gmail.com/ Reported-by: Maximilian Luz Signed-off-by: Rafael J. Wysocki Tested-by: Maximilian Luz Signed-off-by: Sasha Levin --- drivers/pci/pci.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 9e971fffeb6a..e30a70eda562 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1880,11 +1880,7 @@ static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags) * so that things like MSI message writing will behave as expected * (e.g. if the device really is in D0 at enable time). */ - if (dev->pm_cap) { - u16 pmcsr; - pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr); - dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK); - } + pci_update_current_state(dev, dev->current_state); if (atomic_inc_return(&dev->enable_cnt) > 1) return 0; /* already enabled */ -- 2.30.2