commonize log_into_alive_vm code

index 31e2f7c..38bc3be 100644
@@ -9,8 +9,7 @@ import ppm_utils
 import scan_results
 
 
-def run_boot(test, params, env):
-    vm = kvm_utils.env_get_vm(env, params.get("main_vm"))
+def log_into_alive_vm(vm):
     if not vm:
         message = "VM object not found in environment"
         kvm_log.error(message)

@@ -30,6 +29,12 @@ def run_boot(test, params, env):
 
     kvm_log.info("Logged in")
 
+
+def run_boot(test, params, env):
+    vm = kvm_utils.env_get_vm(env, params.get("main_vm"))
+
+    log_into_alive_vm(vm)
+
     if params.get("reboot") == "yes":
         session.sendline(params.get("cmd_reboot"))
         kvm_log.info("Reboot command sent; waiting for guest to go down...")

@@ -202,24 +207,8 @@ def run_migration(test, params, env):
 
 def run_autotest(test, params, env):
     vm = kvm_utils.env_get_vm(env, params.get("main_vm"))
-    if not vm:
-        message = "VM object not found in environment"
-        kvm_log.error(message)
-        raise error.TestError, message
-    if not vm.is_alive():
-        message = "VM seems to be dead; Test requires a living VM"
-        kvm_log.error(message)
-        raise error.TestError, message
 
-    kvm_log.info("Logging into guest...")
-
-    session = kvm_utils.wait_for(vm.ssh_login, 240, 0, 2)
-    if not session:
-        message = "Could not log into guest"
-        kvm_log.error(message)
-        raise error.TestFail, message
-
-    kvm_log.info("Logged in")
+    log_into_alive_vm(vm)
 
     # Collect some info
     test_name = params.get("test_name")

@@ -378,25 +367,8 @@ def internal_yum_update(session, command, prompt, timeout):
 
 
 def run_yum_update(test, params, env):
-    vm = kvm_utils.env_get_vm(env, params.get("main_vm"))
-    if not vm:
-        message = "VM object not found in environment"
-        kvm_log.error(message)
-        raise error.TestError, message
-    if not vm.is_alive():
-        message = "VM seems to be dead; Test requires a living VM"
-        kvm_log.error(message)
-        raise error.TestError, message
-
-    kvm_log.info("Logging into guest...")
 
-    session = kvm_utils.wait_for(vm.ssh_login, 120, 0, 2)
-    if not session:
-        message = "Could not log into guest"
-        kvm_log.error(message)
-        raise error.TestFail, message
-
-    kvm_log.info("Logged in")
+    log_into_alive_vm(vm)
 
     internal_yum_update(session, "yum update", params.get("ssh_prompt"), 600)
     internal_yum_update(session, "yum update kernel", params.get("ssh_prompt"), 600)