On Tue, Oct 2, 2018 at 10:05 AM Pavel Machek <[email protected]> wrote: > > Hi! > > > In general Linux doesn't behave super great if you get an error while > > executing a device's resume handler. Nothing will come along later > > and and try again to resume the device (and all devices that depend on > > it), so pretty much you're left with a non-functioning device and > > that's not good. > > > > However, even though you'll end up with a non-functioning device we > > still don't consider resume failures to be fatal to the system. We'll > > keep chugging along and just hope that the device that failed to > > resume wasn't too critical. This establishes the precedent that we > > should at least try our best not to fully bork the system after a > > resume failure. > > > > I will argue that the best way to keep the system in the best shape is > > to assume that if a resume callback failed that it did as close to > > no-op as possible. Because of this we should consider the device > > still suspended and shouldn't try to suspend the device again next > > time around. Today that's not what happens. AKA if you have a > > device > > I don't think there are many guarantees when device resume fail. It > may have done nothing, and it may have resumed the device almost > fully. > > I guess the best option would be to refuse system suspend after some > device failed like that. > > That leaves user possibility to debug it...
I guess so. Doing that in all cases is kind of risky IMO, because we haven't taken the return values of the ->resume* callbacks into account so far (except for printing the information that is), so there may be non-lethal cases when that happens and the $subject patch would make them not work any more. Thanks, Rafael
