Rechilus - what is it? Idle gossip or informing what others did or said about him?

The question of which halachic authorities hold which position is often not clear. For example the Rambam (Hilchos De'os 7:2) clearly says, "What is the definition of gossip (rachil) that the Torah prohibits? It is someone who takes information about people and spreads it from one person to another and says, "This is what so-and-so said" or "This is what I heard concerning so-and-so." It is a sin even if what he says is true - because gossip destroys the world."... Thus it is obvious that the Rambam views rechilus as idle gossip – not informing. 

However we find that the Kesef Mishna (Hilchos De'os 7:1) disagrees with this conclusion. He says, A person who gossips (rechilus) about another...The view of the Rambam is that rechilus saying "so-and-so said something about you" or "he did something to you" even though the alleged statement or act is not negative or degrading to that person. The classic example of rechilus is what Doeg told Shaul that Achimelech gave bread and the sword of Goliath to Dovid. If you had asked Achimelech whether he had said these things he would not deny them because there is nothing negative about these statements. In fact the opposite is true. He considered that he was properly serving Shaul as can be seen in his defense for saying these things.  So even though the statements contain nothing inherently negative about another person, but since he is spreading the information from one person to another- this is called rechilus because it is like a peddler (rochel) who travels around the cities.

The Kesef Mishnah's understanding is discussed also by Avodas HaMelech (Hilchos De'os 7:2): Gossip (rechilus) is when one says "this is what so-and-so said" or this is what I heard about "so-and-so". See the Kesef Mishna who explains that rechilus according to the Rambam is when says, "So-and-so said about you such and such" or "So-and-so did such and such to you." That even if there is nothing inherently degrading just as we saw concerning the gossip of Doeg who mentioned to Shaul that Achimelech gave bread and the sword of Goliath to Dovid and if he was asked he would not have denied saying it because there was nothing degrading said but in fact he considered that he was doing a favor to Shaul and we see when he defended himself. Therefore even though the information conveyed is not inherently negative to someone but since it was conveyed from one person to another – it is called rechilus (gossip) which is exactly what it is. It is like a peddler traveling around the cities with his wares.<

Thus we see from the Rambam's example of Doeg that he views Rechilus as informing someone what another person had said or done which impacted the listener – and not idle gossip about other people. The Chofetz Chaim accepts this as the correct understanding of the Rambam and what Rechilus is.