I got the endless war sword that does 2d6 extra damage to enemies and 1d6 to the wielder, using it on Amiri who has 2DR from level and 4DR from taking the extra DR feat twice, yet she still takes damage from swining the sword around even tho it should absorb the max roll dmg from that 1D6, this a known bug?

That's a good question. I would say damage reduction only applies to damage caused by an enemy and it's not a bug.

DR should reduce all damage, as least this is the way it is explained at the game&the Pathfinder Rulebook.