Comment 23 for bug 671001

@Epeedk, no, pretty certain not. Unfortunately the generic title of this report will cause many people to believe so. The problem is that the last line of a stack trace is the beginning of functions being called and this will be system_call_fastpath in most of the cases (maybe even always) as that is user-space calling some kernel function. The interesting parts are the top of that trace and unfortunately that is off the screen so often.
In your case this looks like some problem with the interrupt handler of the ene_ir module. And since it did not happen before this is either a now driver or a now bug there. But please, open a new report for that. Maybe check before whether there is always ene_ir present in the trace when boot fails. To open a new bug just run "ubuntu-bug linux" from the running system. Thanks.