Re: Unable to create VM with nic device on Arndale

["Roger Pau Monné" <roger.pau@citrix.com>]

On 17/01/14 12:59, Ian Campbell wrote:
> On Fri, 2014-01-17 at 19:43 +0800, Dennis Lan (dlan) wrote:
>> On Fri, Jan 17, 2014 at 7:01 PM, Ian Campbell <Ian.Campbell@citrix.com> wrote:
>>
>>
>>> vif-bridge and the common scripts which it includes would be a good
>>> start. Just an echo at the top to confirm that the script is running
>>> would be useful.
>>>
>>> I used to do "exec 1>/tmp/hotplug.log 2>&1" at the top to aid debugging
>>> when these scripts were launched by udev, but now that libxl runs them
>>> you may find that the debug from the script comes out on stdout/err of
>>> the xl create command so perhaps that isn't needed any more.
>>>
>>>> headless here.
>>>
>>> That shouldn't matter, you are looking for output from userspace
>>> scripts, not kernel or hypervisor logs.
>>>
>>> Ian.
>>>
>>
>> Hi Ian
>> I suspect for 4.4.0, the network devices even was not detected.
>> this is output from 4.3.1, notes follow lines.
>>
>> libxl: debug: libxl_device.c:959:device_hotplug: calling hotplug
>> script: /etc/xen/scripts/vif-bridge online
>> dlan: vif-bridge start
>> dlan: vif-common start
>>
>> dlan: vif-bridge start -> output from vif-bridge script
>> dlan: vif-common start -> output from vif-common.sh script
> 
> So these are the 4.3 logs? Have you tried 4.4 and found that it doesn't
> produce the same output?
> 
> (please can you try and set the text type to "preformatted" for the logs
> -- having them wrapped makes them very hard to read).
> 
> The lack of 
> libxl: debug: libxl_device.c:959:device_hotplug: calling hotplug script: /etc/xen/scripts/vif-bridge online
> in your original logs is a bit concerning.
> 
> Roger -- any ideas?

My first guess would be that libxl__get_domid failed, however I'm not 
able to reproduce this. I'm attaching a patch to add an error message 
if libxl__get_domid fails, and also prevent the removal of xenstore 
entries so we can see what's going on. Dennis/Eugene, could you try the 
attached patch and send the output of xl -vvv create <...> and 
xenstore-ls -fp after the failed creation?

---
diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
index a604cd8..03f9fe9 100644
--- a/tools/libxl/libxl_create.c
+++ b/tools/libxl/libxl_create.c
@@ -1296,6 +1296,9 @@ static void domcreate_complete(libxl__egc *egc,
         rc = xc_flask_relabel_domain(CTX->xch, dcs->guest_domid, d_config->b_info.exec_ssidref);
 
     if (rc) {
+        LOG(ERROR, "domain creation failed, not doing removal of xs entries");
+        dcs->callback(egc, dcs, rc, -1);
+        return;
         if (dcs->guest_domid) {
             dcs->dds.ao = ao;
             dcs->dds.domid = dcs->guest_domid;
diff --git a/tools/libxl/libxl_device.c b/tools/libxl/libxl_device.c
index ba7d100..56d8162 100644
--- a/tools/libxl/libxl_device.c
+++ b/tools/libxl/libxl_device.c
@@ -965,7 +965,10 @@ static void device_hotplug(libxl__egc *egc, libxl__ao_device *aodev)
      * hotplug scripts
      */
     rc = libxl__get_domid(gc, &domid);
-    if (rc) goto out;
+    if (rc) {
+        LOG(ERROR, "unable to get domain id, error: %d", rc);
+        goto out;
+    }
     if (aodev->dev->backend_domid != domid) {
         if (aodev->action != LIBXL__DEVICE_ACTION_REMOVE)
             goto out;