It looks like there may be a fix upstream in the form of commit a682604838763981613e42015cd0e39f2989d6bb "rcu: Teach RCU that idle task is not quiscent state at boot".
It looks like there may be a fix upstream in the form of commit a68260483876398 1613e42015cd0e3 9f2989d6bb "rcu: Teach RCU that idle task is not quiscent state at boot".