White Mushroom

There are several types of plants that need a host to grow. Live tree or dead tree can be used as its host.
One of the plants that the host needs is a mushroom. There are 2 types of mushrooms, namely edible mushrooms and mushrooms that can not be eaten (toxic). But, I do not know which mushrooms to eat and which ones can not be eaten.
Mushroom size is also a lot, from the smallest to large.

So, I post a mushroom. I think the size of this mushroom is small. I do not know this mushroom can be eaten or not. But, I feel this fungus is poisonous. Because, this fungus grows on the rotting tree trunk.