I am trying to get php-fpm to process php files from nginx. Nginx is configured as follows

location ~ \.php$ {
try_files $uri =404;
include fastcgi_params;
fastcgi_pass unix:/var/run/php.socket;
# fastcgi_pass 127.0.0.1:9000;
}

If I put in a bogus page, I get a not found 404, which indicates the location block is being exected. However, real php pages just display nothing. I turned up logging to debug for php-fpm and fastcgi.logging = 1, but nothing is logged except

[20-Mar-2017 01:50:02.193330] DEBUG: pid 14906, fpm_pctl_perform_idle_server_maintenance(), line 379: [pool www] currently 0 active children, 2 spare children, 2 running children. Spawning rate 1

I tried both the unix socket and the tcp port. The behavior is the same.