PSL_AC
| PSL_D | PSL_V | PSL_NT | PSL_AC | PSL_ID)
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);
if (frame->tf_rflags & PSL_AC)
(frame->tf_rflags & PSL_AC) == 0) {