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=ham 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 44343C433F5 for ; Thu, 9 Sep 2021 13:02:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2EE8C61167 for ; Thu, 9 Sep 2021 13:02:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352600AbhIINDt (ORCPT ); Thu, 9 Sep 2021 09:03:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:43558 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357131AbhIIM7j (ORCPT ); Thu, 9 Sep 2021 08:59:39 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E41E063270; Thu, 9 Sep 2021 11:59:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631188744; bh=9ltp730vYWmSMGHKY4vhC+wk7KxXAoiZxzTw7xhg6fk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FppZPamUPu5mbwCXhMmLbIVT0OMwFsNWfR11vBWVxQTNHOBjnNlOAnny6P5A81Fb0 X5U5+7In2e1gOIdhzP8naQwGmWANtcAeLUMasfl9Vz1sKJwvAw4FqTdRaQctg7PaZS EpTNHuP9pFpoceuOkl1P9ASuKFzWW14Wqn7cz/GUN0PqGsLsEL1ROY3HqJxlHEWRs+ bsHrY6g6EeESP5ser9shIuHf1EcX3Mt6YUtHnTnJRGJYhPzBgYiiAkfWPiS8Sh0LlG ykw+mrThFxOjhBzMSFXHimH6LIstrkFkOwSEZuKlBKQqeKyhwDZ3BysL84TNwfNvsV LwnCBFhMSfMkA== 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 4.14 03/59] PCI: Use pci_update_current_state() in pci_enable_device_flags() Date: Thu, 9 Sep 2021 07:58:04 -0400 Message-Id: <20210909115900.149795-3-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210909115900.149795-1-sashal@kernel.org> References: <20210909115900.149795-1-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: stable@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 c847b5554db6..893e1e8e5bd1 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1384,11 +1384,7 @@ 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