centos7+django+uwsgi+nginx访问报错

报错如下：

2016/05/13 19:02:40 [error] 11057#0: *162 upstream prematurely closed connection while reading 
response header from upstream, client: xxx.xxx.xxx.xxx, server: xxx.xxx.xxx.xxx, request: "GET 
/poweredby.png HTTP/1.1", upstream: "uwsgi://127.0.0.1:8003", host: "xxx.xxx.xxx.xxx:8000", 
referrer: "http://xxx.xxx.xxx.xxx:8000/"
uwsgi 配置如下：

[uwsgi]
socket = 127.0.0.1:8003
touch-reload=/myblog/reload

processes = 2
threads = 4
vacuum = true
nginx 配置如下：

 server {
        listen       8000;
        server_name  xxx.xxx.xxx.xxx;
        root         /usr/share/nginx/html;
        access_log /logs/access.log;
        error_log /logs/error.log;

        charset     utf-8;

        # Load configuration files for the default server block.

        location / {
            include  /etc/nginx/uwsgi_params;
            uwsgi_pass  127.0.0.1:8003;
            client_max_body_size 35m;
            uwsgi_param UWSGI_SCRIPT myblog.wsgi;
            uwsgi_param UWSGI_CHDIR /myblog;
        }
        location /media  {
            alias /path/to/project/media;
        }

        location /static {
            alias /path/to/project/static;
        }

        error_page 404 /404.html;
            location = /40x.html {
        }

        error_page 500 502 503 504 /50x.html;
            location = /50x.html {
        }
    }
views.py 文件内容

#coding:utf-8
from django.shortcuts import render
from django.http import HttpResponse

# Create your views here.
def index(request):
    return HttpResponse(u"Hello World!!")

搞了一天了，死活连不上， uwsgi8003 端口正常访问， nginx 代理 8000 端口连不上，端口已经开放，防火墙已经关闭，求解,感激不尽！