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Subject: Re: [RFC][PATCH] fix move/migrate_pages() race on task struct
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Oh and another thing. There are certain functions that are now called
under rcu read lock()

	security_task_movememory

and

	cpuset_mems_allowed


cpuset_mems_allowed takes a mutex. Hmmm... Under rcu?

security_task_movememory does some kind of security hook.


Is that all safe? If not then we need to take a refcount on the task
struct after all.