If you have knives that you put through the dishwasher way too many times and they start to rust immediately after you remove the rust and dishwasher them again, there is a solution. I started hearing alot about bad stainless steel and stuff but I thought what the hell is going on, they used to be fine.
So I made a 25% citric acid solution in a pot made with filtered water, scrubbed the knives clean with a scotch brite and barkeepers friend, then I rinsed them good with hot water and poured the hot citric acid water (like 50 degree C) into a ceramic rectangle bread pan after stacking the knives in there so they occupy the least area. After a 0.5 hour soak the water turned a little bit iron color, so I took the knives out and rinsed them good with hot water.
On the next dishwasher cycle I only had very minor corrosion stains. I think with a longer soak and some temperature control (oven set to low) you can re-passivate them very nicely. It was good enough for me. Throwing them into the dishwasher with a bunch of citric acid powder might work too and also clean your dishwasher, but I am not sure.