Prepare cake batter. Preheat oven to 350 degrees. Bake walnuts in a single layer in a shallow pan 8 to 10 minutes or until toasted and fragrant, stirring halfway through (if desired - not necessary to toast nuts).
Stir together flour, sugar, baking soda, cinnamon and salt in a large bowl. Stir in eggs, bananas, crushed pineapple and oil, stirring just until dry ingredients are moistened. Stir in nuts. Spoon batter into greased and floured Bundt pan.
Bake at 350 degrees for 1 hour or until a long wooden pick inserted in center comes out clean. Cool cake in pan on a wire rack 15 minutes; remove from pan to wire rack, and cool completely (about 2 hours)
Prepare glaze: Process cream cheese, powdered sugar, vanilla, and 1 tablespoon milk in a food processor until well blended. Add remaining 1 tablespoon milk, 1 teaspoon at a time, processing until smooth. Immediately pour glaze over cooled cake, and sprinkle with remaining 1/2 cup nuts.