On Wednesday, September 03, 2014 06:02:19 PM Brian Norris wrote: > Hi, > > If I enable CONFIG_PM_DEBUG on a 3.14.y kernel, I can see the following > results: > > # cat /sys/power/state > freeze standby mem > # cat /sys/power/pm_test > [none] core processors platform devices freezer > # echo core > /sys/power/pm_test > # cat /sys/power/state > [ 22.581289] Unsupported pm_test mode for freeze state, please choose none/freezer/devices/platform. > standby mem > > Note how 'freeze' is dropped from the supported states, and I get an > extra printk message when I'm just checking if the state is valid. > > It looks like if I backport a few fixes, I get more sane behavior, where > the warnings (and -EAGAIN) appear only when I actually try to enter an > unsupported test mode: > > # echo core > /sys/power/pm_test > # cat /sys/power/state > freeze standby mem > # echo freeze > /sys/power/state > [ 27.833141] PM: Unsupported test mode for freeze state,please choose none/freezer/devices/platform. > sh: echo: write error: Resource temporarily unavailable > > I think I've narrowed it down to this commit that should be backported > to -stable (for 3.9+?): > > 43e8317b0bba PM / sleep: Use valid_state() for platform-dependent sleep states only > > But it needs to drag along this dependency too: > > 27ddcc6596e5 PM / sleep: Add state field to pm_states[] entries That sounds OK. Can you please send a formal request to include the two commits above to Greg/stable? > While at this, it looks like this commit might be deserving of -stable > (3.9+). I haven't tested this one, as I don't have a good freeze+cpuidle > setup; it just shows up in the commit log with an interesting > description and a 'Fixes' tag: > > f3f125324fc1 PM / suspend: Make cpuidle work in the "freeze" state Well, it basically makes the freeze state save energy, but it's not essential. I'm not seeing the "Fixes:" tag on it, though. Rafael -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html