After using Camera Raw and Photoshop for a while, the image becomes a patchwork of the original image and black or white squares.

Solution

1. Update Camera Raw to version 9.3.1
2. Restart Photoshop

Solution 2

Disable "Use Graphics Processor" in the Camera Raw preferences.

1. Preferences > Camera Raw...
2. Uncheck "Use Graphics Processor" in the performance section of the dialog
3. Restart Photoshop