If you already have hsv1, you have antibodies that protect you from getting it again. Do you have it orally? You definitely can't get it again in the same location.
If you have it genitally, I might still not expose myself orally to anyone with visible outbreaks, because it's most infectious then, but you should be fine. Avoid exposures to open sores - you don't really know what's causing them.
Also, herpes doesn't go from the genitals to the mouth as easily as it does from the mouth to the genitals.