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to use check_add_overflow(). > Commit 6014bc27561f2 relaxed the checks in x86-64's access_ok() and added > an explicit check for TASK_SIZE here to make up for it. > That left a pointless access_ok() call with its associated 'lfence' that > can never actually fail. > So just delete the test. > > Signed-off-by: David Laight > --- > mm/gup.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) Reviewed-by: Jason Gunthorpe I often wonder about about access_ok() calls, if they still do anything.. Jason