Backporting "padata: Remove broken queue flushing"

I noticed that commit 07928d9bfc81 "padata: Remove broken queue flushing" has been backported to most stable branches, but commit 6fc4dbcf0276 "padata: Replace delayed timer with immediate workqueue in padata_reorder" has not.

Is this correct? What prevents the parallel_data ref-count from dropping to 0 while the timer is scheduled?

Ben.