Jesus made preparations for Passover even though He was fully aware that one of His disciples, namely Judas Iscariot would betray Him.
On the first day of unleavened bread Jesus disciples asked Jesus, where he wanted to go to eat the passover meal. Mark 14:12 NIV
And Jesus sent two of his disciples and said, "Go ye into the city, and there shall meet you a man bearing a pitcher of water, follow him. Mark14:13 NIV
And wheresoever he shall go in, say ye to the goodsman of the house, The Master saith, Where is the guest chamber, where I shall eat the passover with my disciples Mark 14:14 NIV
And he will show you a large upper room furnished and prepared: there make ready for us". Mark 14:15 NIV
​And He answered and said unto them. "It is one of the twelve, that dippeth with me in the dish. Mark 14:20
The Son of man indeed goeth, as it is written of him: but woe to that man by whom the Son of man is betrayed! good were it for that man if he had never been born." Mark 14:21
And as they did eat, Jesus took bread, and blessed, and brake it and gave to them and said, "Take, eat: this is my body" Mark 14:22
​And as they sat and did eat, Jesus said , "Verily I say unto you, One of you which eateth with me shall betray me." Mark 14:18 
​And they began to be sorrowful, and say unto him one by one, Is it I? and another said, Is it I? Mark 14:19
Jesus knew prior to His death that He would be betrayed by Judas Iscariot because before His death Jesus washed the feet of His disciples and when He was finished He talked to them telling them that one of them would betray Him.
For he knew who should betray him; therefore said he, Ye are not all clean. John 13:11
After washing His disciples feet Jesus again spoke of Judas upcoming betrayal.