[PATCH 3.19.y-ckt 85/99] PM / sleep: Handle failures in device_suspend_late() consistently

From: Kamal Mostafa
Date: Thu Jul 07 2016 - 14:45:14 EST


3.19.8-ckt23 -stable review patch. If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: "Rafael J. Wysocki" <rafael.j.wysocki@xxxxxxxxx>

commit 3a17fb329da68cb00558721aff876a80bba2fdb9 upstream.

Grygorii Strashko reports:

The PM runtime will be left disabled for the device if its
.suspend_late() callback fails and async suspend is not allowed
for this device. In this case device will not be added in
dpm_late_early_list and dpm_resume_early() will ignore this
device, as result PM runtime will be disabled for it forever
(side effect: after 8 subsequent failures for the same device
the PM runtime will be reenabled due to disable_depth overflow).

To fix this problem, add devices to dpm_late_early_list regardless
of whether or not device_suspend_late() returns errors for them.

That will ensure failures in there to be handled consistently for
all devices regardless of their async suspend/resume status.

Reported-by: Grygorii Strashko <grygorii.strashko@xxxxxx>
Tested-by: Grygorii Strashko <grygorii.strashko@xxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
drivers/base/power/main.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 9717d5f..508a8f6 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -1251,14 +1251,15 @@ int dpm_suspend_late(pm_message_t state)
error = device_suspend_late(dev);

mutex_lock(&dpm_list_mtx);
+ if (!list_empty(&dev->power.entry))
+ list_move(&dev->power.entry, &dpm_late_early_list);
+
if (error) {
pm_dev_err(dev, state, " late", error);
dpm_save_failed_dev(dev_name(dev));
put_device(dev);
break;
}
- if (!list_empty(&dev->power.entry))
- list_move(&dev->power.entry, &dpm_late_early_list);
put_device(dev);

if (async_error)
--
2.7.4