4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Sudeep Holla <[email protected]> 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 <[email protected]> Acked-by: Ulf Hansson <[email protected]> Signed-off-by: Rafael J. Wysocki <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/base/power/domain.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1029,8 +1029,6 @@ static struct generic_pm_domain_data *ge spin_unlock_irq(&dev->power.lock); - dev_pm_domain_set(dev, &genpd->domain); - return gpd_data; err_free: @@ -1044,8 +1042,6 @@ static struct generic_pm_domain_data *ge static void genpd_free_dev_data(struct device *dev, struct generic_pm_domain_data *gpd_data) { - dev_pm_domain_set(dev, NULL); - spin_lock_irq(&dev->power.lock); dev->power.subsys_data->domain_data = NULL; @@ -1082,6 +1078,8 @@ static int genpd_add_device(struct gener if (ret) goto out; + dev_pm_domain_set(dev, &genpd->domain); + genpd->device_count++; genpd->max_off_time_changed = true; @@ -1143,6 +1141,8 @@ static int genpd_remove_device(struct ge if (genpd->detach_dev) genpd->detach_dev(genpd, dev); + dev_pm_domain_set(dev, NULL); + list_del_init(&pdd->list_node); mutex_unlock(&genpd->lock);
