Malphite and Rammus are especially good counters to her. Of course, not directly in the lane. But Jinx does not fare very well because both are tanks who stack a lot of armor while benefiting from it, and Jinx's damage is exclusively physical.
She already has a low base attack speed, and Malphite's E can reduce it to abysmal levels. On top of that, Malphite's ult make it so that Jinx is extremely easy to focus. Unless Jinx has a Banshee's Veil, she can't avoid it.
As for Rammus, she can't easily escape from him, thanks to his enormous MS boost from his Q. Then, once Jinx is taunted, she will die easily because she can't stand up against Rammus' W and his ult, especially if Rammus has Thornmail to further boost that damage.
Malphite can also buy Thornmail, and shut down Jinx.
I hope that this helps.