testb
testb $SEL_RPL_MASK,TF_CS(%rsp) ; /* come from kernel? */ \
testb $SEL_RPL_MASK,TF_CS(%rsp) ; /* come from kernel? */ \
extern int testb(size_t, uint_t);
testb $0x1, PCB_RUPDATE(%r15); \
testb $0xff, VCPU_INFO_EVTCHN_UPCALL_PENDING(r)
testb $1, VCPU_INFO_EVTCHN_UPCALL_MASK(r)