4.4-stable review patch. If anyone has any objections, please let me know.
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From: Rafael J. Wysocki rafael.j.wysocki@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 alcooperx@gmail.com Tested-by: Al Cooper alcooperx@gmail.com Reviewed-by: Ulf Hansson ulf.hansson@linaro.org Cc: 3.16+ stable@vger.kernel.org # 3.16+ Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@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 @@ -1355,8 +1355,10 @@ 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 @@ -1368,6 +1370,7 @@ 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; }