Messages in this thread Patch in this message | | | From | Greg Kroah-Hartman <> | Subject | [PATCH 4.12 190/196] PM / Domains: defer dev_pm_domain_set() until genpd->attach_dev succeeds if present | Date | Tue, 25 Jul 2017 12:23:09 -0700 |
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4.12-stable review patch. If anyone has any objections, please let me know.
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From: Sudeep Holla <Sudeep.Holla@arm.com>
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 <sudeep.holla@arm.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- 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 @@ -1168,8 +1168,6 @@ 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: @@ -1183,8 +1181,6 @@ 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; @@ -1221,6 +1217,8 @@ 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; @@ -1282,6 +1280,8 @@ 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); genpd_unlock(genpd);
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