On Fri, May 28, 2010 at 02:55:26PM +0100, Alan Cox wrote: > The following cannot occur on my laptop for simple idling > > Alarm > Suspend > > because the Alarm resets the suspend timer when it is delivered. Userspace is about to write to /sys/power/state when it gets scheduled. Alarm delivery occurs at that instant. Kernel has no idea that it's about to go to sleep, so the driver handles things appropriately and clears the hardware state. Userspace gets scheduled, writes and the system suspends. The problem is that having userspace decidie to initiate a suspend and then actually initiate a suspend isn't an atomic operation. -- Matthew Garrett | mjg59@xxxxxxxxxxxxx _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm