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Consider two devices, A and B, where B is a child of A, and B utilizes asynchronous suspend (it does not matter whether A is sync or async). If B fails to suspend_noirq() or suspend_late(), or is interrupted by a wakeup (pm_wakeup_pending()), then it aborts and sets the async_error variable. However, device A does not (immediately) check the async_error variable; it may continue to run its own suspend_noirq()/suspend_late() callback. This is bad. We can resolve this problem by doing our error and wakeup checking (particularly, for the async_error flag) after waiting for children to suspend, instead of before. This also helps align the logic for the noirq and late suspend cases with the logic in __device_suspend(). It's easy to observe this erroneous behavior by, for example, forcing a device to sleep a bit in its suspend_noirq() (to ensure the parent is waiting for the child to complete), then return an error, and watch the parent suspend_noirq() still get called. (Or similarly, fake a wakeup event at the right (or is it wrong?) time.) Fixes: |
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| .. | ||
| opp | ||
| clock_ops.c | ||
| common.c | ||
| domain_governor.c | ||
| domain.c | ||
| generic_ops.c | ||
| main.c | ||
| Makefile | ||
| power.h | ||
| qos.c | ||
| runtime.c | ||
| sysfs.c | ||
| trace.c | ||
| wakeirq.c | ||
| wakeup.c | ||