Also stumbled on the max_file_size problem, in particular getting no response, no error whatsoever when uploading a file bigger than the set upload_max_filesize.
I found that it's not the upload_max_filesize setting, but instead the post_max_size setting causing this no response issue. So if you set post_max_size way larger than upload_max_filesize, at least you are likely to get an error response when filesize exceeds upload_max_filesize but is still within the limits of post_max_size.
Hope this helps anyone.
