Can someone give me some tips laning vs him. I play a lot of ahri and it seems like whenever I go in post 6 he just ults me anytime I get lower than 3/4 health and just cleans up the kills. Also his poison spreading is pretty annoying. I know I'm not good I'm just looking for advice.
The main thing is post 6, never engage Malzahar 1v1. He will win because of his ult. One thing you can do is ask for a gank, Malzahar naturally pushes waves or runs OoM since he has to keep killing things with his damage over time to restore it. Thus he is a very easy champion to gank.
Just don't get into his ulting range and he is easy to pick off. Don't dash into his face, dash around him and kill him.
or 
You buy a QSS. You win because now his ult is useless.
Until then just farm and only engage when you jungler comes, it is possible to use your charm to interrupt his ult but you need to cast it before his ult suppresses you, then your charm will land after his cast and ruin his channel and burn his cd, then just do Ahri things and stomp him
