Check presence of files under /proc before opening them

library/setup

@@ -967,6 +967,7 @@ class LinuxVirtual(Virtual):
             self.facts['virtualization_role'] = 'guest'
             return
 
+        if os.path.exists('/proc/self/status'):
             for line in open('/proc/self/status').readlines():
                 if re.match('^VxID: \d+', line):
                     self.facts['virtualization_type'] = 'linux_vserver'
@@ -976,6 +977,7 @@ class LinuxVirtual(Virtual):
                         self.facts['virtualization_role'] = 'guest'
                     return
 
+        if os.path.exists('/proc/cpuinfo'):
             for line in open('/proc/cpuinfo').readlines():
                 if re.match('^model name.*QEMU Virtual CPU', line):
                     self.facts['virtualization_type'] = 'kvm'