On Wed, Jan 09, 2019 at 12:47:37PM +0100, Sebastian Andrzej Siewior wrote: > Add TIF_NEED_FPU_LOAD. This is reserved for loading the FPU registers > before returning to userland. This flag must not be set for systems > without a FPU. > If this flag is cleared, the CPU's FPU register hold the current content > of current()'s FPU register. The in-memory copy (union fpregs_state) is > not valid. > If this flag is set, then all of CPU's FPU register may hold a random > value (except for PKRU) and it is required to load the content of the > FPU register on return to userland. This definitely needs to be written somewhere in arch/x86/include/asm/fpu/internal.h or where we decide to put the FPU handling rules. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.