ptrace_read_regs
ret = ptrace_read_regs(pid, NT_PPC_PKEY, regs, 3);
ret = ptrace_read_regs(pid, NT_PPC_PKEY, regs, 3);
ret = ptrace_read_regs(pid, NT_PPC_PKEY, regs, 3);
ret = ptrace_read_regs(pid, NT_PPC_PKEY, regs, 3);