On 03/29, Gregory Price wrote: > > Last note on this before I push up another patch set. > > The change from __get_user to get_user also introduces a call to > might_fault() which adds a larger callstack for every syscall / > dispatch. This turns into a might_sleep and might_reschedule, which > represent a very different pattern of execution from before. might_fault() is nop unless CONFIG_PROVE_LOCKING || DEBUG_ATOMIC_SLEEP. Again, I won't really argue with task_access_ok(). Just I am not sure 2/4 gives enough justification for this new helper with unclear semantics (until we ensure that access_ok() doesn't depend on current). Oleg.