On 18/09/2018 16:27, Sebastian Andrzej Siewior wrote: >> Likewise, move this to fpu__clear and outside "if >> (static_cpu_has(X86_FEATURE_FPU))"? > okay. But if there is no FPU we did not save/restore the pkru value. Is > this supposed to be an improvement? Honestly it just seemed "more correct", but now that I think about it, kernel threads should run with PKRU=0. maybe there's a preexisting bug that your patch has the occasion to fix. Paolo >> Also, a __read_pkru() seems to be missing in switch_fpu_prepare. > But the value is stored during write_pkru(). So the copy that is saved > should be identical to the value that would be read, correct? >
