PSL_IOPL
curthread->td_lwp->lwp_md.md_regs->tf_rflags |= PSL_IOPL;
curthread->td_lwp->lwp_md.md_regs->tf_rflags &= ~PSL_IOPL;
wrmsr(MSR_SF_MASK, PSL_NT|PSL_T|PSL_I|PSL_C|PSL_D|PSL_IOPL|PSL_AC);
wrmsr(MSR_SF_MASK, PSL_NT|PSL_T|PSL_I|PSL_C|PSL_D|PSL_IOPL|PSL_AC);
curthread->td_lwp->lwp_md.md_regs->tf_rflags |= PSL_IOPL;
curthread->td_lwp->lwp_md.md_regs->tf_rflags &= ~PSL_IOPL;
kprintf("IOPL = %ld\n", (frame->tf_rflags & PSL_IOPL) >> 12);
kprintf("IOPL = %jd\n", (intmax_t)((frame->tf_rflags & PSL_IOPL) >> 12));