From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754187AbdHDXzB (ORCPT ); Fri, 4 Aug 2017 19:55:01 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:48546 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753466AbdHDX1f (ORCPT ); Fri, 4 Aug 2017 19:27:35 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sudeep Holla , Ulf Hansson , "Rafael J. Wysocki" Subject: [PATCH 4.4 36/91] PM / Domains: defer dev_pm_domain_set() until genpd->attach_dev succeeds if present Date: Fri, 4 Aug 2017 16:15:32 -0700 Message-Id: <20170804231557.938166090@linuxfoundation.org> X-Mailer: git-send-email 2.13.4 In-Reply-To: <20170804231555.678888089@linuxfoundation.org> References: <20170804231555.678888089@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 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sudeep Holla commit 975e83cfb8dc16e7a2fdc58188c77c0c605876c2 upstream. If the genpd->attach_dev or genpd->power_on fails, genpd_dev_pm_attach may return -EPROBE_DEFER initially. However genpd_alloc_dev_data sets the PM domain for the device unconditionally. When subsequent attempts are made to call genpd_dev_pm_attach, it may return -EEXISTS checking dev->pm_domain without re-attempting to call attach_dev or power_on. platform_drv_probe then attempts to call drv->probe as the return value -EEXIST != -EPROBE_DEFER, which may end up in a situation where the device is accessed without it's power domain switched on. Fixes: f104e1e5ef57 (PM / Domains: Re-order initialization of generic_pm_domain_data) Signed-off-by: Sudeep Holla Acked-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/base/power/domain.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1188,7 +1188,6 @@ static struct generic_pm_domain_data *ge } dev->power.subsys_data->domain_data = &gpd_data->base; - dev->pm_domain = &genpd->domain; spin_unlock_irq(&dev->power.lock); @@ -1207,7 +1206,6 @@ static void genpd_free_dev_data(struct d { spin_lock_irq(&dev->power.lock); - dev->pm_domain = NULL; dev->power.subsys_data->domain_data = NULL; spin_unlock_irq(&dev->power.lock); @@ -1248,6 +1246,8 @@ int __pm_genpd_add_device(struct generic if (ret) goto out; + dev->pm_domain = &genpd->domain; + genpd->device_count++; genpd->max_off_time_changed = true; @@ -1299,6 +1299,8 @@ int pm_genpd_remove_device(struct generi if (genpd->detach_dev) genpd->detach_dev(genpd, dev); + dev->pm_domain = NULL; + list_del_init(&pdd->list_node); mutex_unlock(&genpd->lock);