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

------------------

From: Rafael J. Wysocki <rafael.j.wyso...@intel.com>

commit 69e445ab8b66a9f30519842ef18be555d3ee9b51 upstream.

If __device_suspend() runs asynchronously (in which case the device
passed to it is in dpm_suspended_list at that point) and it returns
early on an error or pending wakeup, and the power.direct_complete
flag has been set for the device already, the subsequent
device_resume() will be confused by that and it will call
pm_runtime_enable() incorrectly, as runtime PM has not been
disabled for the device by __device_suspend().

To avoid that, clear power.direct_complete if __device_suspend()
is not going to disable runtime PM for the device before returning.

Fixes: aae4518b3124 (PM / sleep: Mechanism to avoid resuming runtime-suspended 
devices unnecessarily)
Reported-by: Al Cooper <alcoop...@gmail.com>
Tested-by: Al Cooper <alcoop...@gmail.com>
Reviewed-by: Ulf Hansson <ulf.hans...@linaro.org>
Cc: 3.16+ <sta...@vger.kernel.org> # 3.16+
Signed-off-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/base/power/main.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -1360,8 +1360,10 @@ static int __device_suspend(struct devic
 
        dpm_wait_for_children(dev, async);
 
-       if (async_error)
+       if (async_error) {
+               dev->power.direct_complete = false;
                goto Complete;
+       }
 
        /*
         * If a device configured to wake up the system from sleep states
@@ -1373,6 +1375,7 @@ static int __device_suspend(struct devic
                pm_wakeup_event(dev, 0);
 
        if (pm_wakeup_pending()) {
+               dev->power.direct_complete = false;
                async_error = -EBUSY;
                goto Complete;
        }


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