DR_TRAP_BITS
if ((dr6 & DR_TRAP_BITS) == 0)
if ((current->thread.virtual_dr6 & DR_TRAP_BITS) ||
(dr6 & (~DR_TRAP_BITS)))
if (dr6 & (DR_STEP | DR_TRAP_BITS) || icebp)
dr6 &= ~DR_TRAP_BITS;
vcpu->arch.dr6 &= ~DR_TRAP_BITS;