On 14/11/2017 20:40, David Hildenbrand wrote: > I think we should check all get/put_fpu callers if they need > preempt_disable(). > > E.g. em_fxrstor() needs disabled preemption as we temporarily > save + restore some host register (via fxsave + fxrstor) under some > circumstances that are not saved/restored when switching to/back from > another process. We should double check.
Rik may correct me, but I believe that you don't need preempt_disable/enable because preempt notifiers do this for you. Paolo
