From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964984AbeEJNDr (ORCPT ); Thu, 10 May 2018 09:03:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:41626 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934380AbeEJNDp (ORCPT ); Thu, 10 May 2018 09:03:45 -0400 Date: Thu, 10 May 2018 08:03:43 -0500 From: Bjorn Helgaas To: "Rafael J. Wysocki" Cc: Joseph Salisbury , bhelgaas@google.com, linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, "linux-kernel@vger.kernel.org" , 1745646@bugs.launchpad.net, Mika Westerberg Subject: Re: [PATCH] PCI / PM: Check device_may_wakeup() in pci_enable_wake() Message-ID: <20180510130343.GA173327@bhelgaas-glaptop.roam.corp.google.com> References: <56a8953c-d833-837c-57d5-fe758d4db02a@canonical.com> <1823373.ea0yBGqyI6@aspire.rjw.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1823373.ea0yBGqyI6@aspire.rjw.lan> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 09, 2018 at 12:18:32AM +0200, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki > > Commit 0847684cfc5f0 (PCI / PM: Simplify device wakeup settings code) > went too far and dropped the device_may_wakeup() check from > pci_enable_wake() which causes wakeup to be enabled during system > suspend, hibernation or shutdown for some PCI devices that are not > allowed by user space to wake up the system from sleep (or power off). > > As a result of this excessive power is drawn by some of the affected > systems while in sleep states or off. > > Restore the device_may_wakeup() check in pci_enable_wake(), but make > sure that the PCI bus type's runtime suspend callback will not call > device_may_wakeup() which is about system wakeup from sleep and not > about device wakeup from runtime suspend. > > Fixes: 0847684cfc5f0 (PCI / PM: Simplify device wakeup settings code) > Reported-by: Joseph Salisbury > Signed-off-by: Rafael J. Wysocki Acked-by: Bjorn Helgaas 0847684cfc5f0 appeared in v4.13, which raises the question of whether this problem is important enough for a stable backport. Up to you :) > --- > drivers/pci/pci.c | 29 +++++++++++++++++++++++------ > 1 file changed, 23 insertions(+), 6 deletions(-) > > Index: linux-pm/drivers/pci/pci.c > =================================================================== > --- linux-pm.orig/drivers/pci/pci.c > +++ linux-pm/drivers/pci/pci.c > @@ -1910,7 +1910,7 @@ void pci_pme_active(struct pci_dev *dev, > EXPORT_SYMBOL(pci_pme_active); > > /** > - * pci_enable_wake - enable PCI device as wakeup event source > + * __pci_enable_wake - enable PCI device as wakeup event source > * @dev: PCI device affected > * @state: PCI state from which device will issue wakeup events > * @enable: True to enable event generation; false to disable > @@ -1928,7 +1928,7 @@ EXPORT_SYMBOL(pci_pme_active); > * Error code depending on the platform is returned if both the platform and > * the native mechanism fail to enable the generation of wake-up events > */ > -int pci_enable_wake(struct pci_dev *dev, pci_power_t state, bool enable) > +static int __pci_enable_wake(struct pci_dev *dev, pci_power_t state, bool enable) > { > int ret = 0; > > @@ -1969,6 +1969,23 @@ int pci_enable_wake(struct pci_dev *dev, > > return ret; > } > + > +/** > + * pci_enable_wake - change wakeup settings for a PCI device > + * @pci_dev: Target device > + * @state: PCI state from which device will issue wakeup events > + * @enable: Whether or not to enable event generation > + * > + * If @enable is set, check device_may_wakeup() for the device before calling > + * __pci_enable_wake() for it. > + */ > +int pci_enable_wake(struct pci_dev *pci_dev, pci_power_t state, bool enable) > +{ > + if (enable && !device_may_wakeup(&pci_dev->dev)) > + return -EINVAL; > + > + return __pci_enable_wake(pci_dev, state, enable); > +} > EXPORT_SYMBOL(pci_enable_wake); > > /** > @@ -1981,9 +1998,9 @@ EXPORT_SYMBOL(pci_enable_wake); > * should not be called twice in a row to enable wake-up due to PCI PM vs ACPI > * ordering constraints. > * > - * This function only returns error code if the device is not capable of > - * generating PME# from both D3_hot and D3_cold, and the platform is unable to > - * enable wake-up power for it. > + * This function only returns error code if the device is not allowed to wake > + * up the system from sleep or it is not capable of generating PME# from both > + * D3_hot and D3_cold and the platform is unable to enable wake-up power for it. > */ > int pci_wake_from_d3(struct pci_dev *dev, bool enable) > { > @@ -2114,7 +2131,7 @@ int pci_finish_runtime_suspend(struct pc > > dev->runtime_d3cold = target_state == PCI_D3cold; > > - pci_enable_wake(dev, target_state, pci_dev_run_wake(dev)); > + __pci_enable_wake(dev, target_state, pci_dev_run_wake(dev)); > > error = pci_set_power_state(dev, target_state); > >