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> "fixed_percpu_data is not at start of per-cpu area"); > #endif > > +#ifdef CONFIG_RETHUNK > +. = ASSERT((__x86_return_thunk & 0x3f) == 0, "__x86_return_thunk not cacheline-aligned"); Probably best to say 64b aligned.  The safety property is to do with the layout of the BTB, not of a cacheline. FWIW, Reviewed-by: Andrew Cooper