Re: Issues with latest staging tree starting PV guest.

[Mukesh Rathor <mukesh.rathor@oracle.com>]

On Mon, 3 Mar 2014 18:52:39 -0800
Mukesh Rathor <mukesh.rathor@oracle.com> wrote:

> Hi,
... 
>   3. I setup xenbr, added vif line as always:
>         vif = ['type=netfront,bridge=xenbr0']
> 
>     But now get:
>      libxl: error: libxl_create.c:1226:domcreate_attach_vtpms: unable
>     to add nic devices

This is how far I got debugging this:

Looks like the issue is not getting domid, because stepping thru I see
in devstate_watch_callback() it goes thru:

    } else {
        int got = atoi(sstate);
        if (got == ds->wanted) {
            LIBXL__LOG(CTX, LIBXL__LOG_DEBUG, "backend %s wanted state %d ok",
                       watch_path, ds->wanted);
            rc = 0;
logging:
libxl: debug: libxl_event.c:653:devstate_watch_callback: backend /local/domain/0/backend/vif/5/0/state wanted state 2 ok

then it calls:
...
ds->callback(egc, ds, rc); --> device_backend_callback --> device_hotplug
which does:
...
    rc = libxl__get_domid(gc, &domid);  ---> libxl__xs_read_checked
     --> libxl__xs_read (, , path="domid")...
      This returns result == 0 and errno == ENOENT.

logging:
libxl: debug: libxl_dm.c:1473:kill_device_model: Device Model signaled
libxl: error: libxl_device.c:780:libxl__initiate_device_remove: unable to get my domid

However, xenstore-ls, I see domid being there:
  bash> xenstore-ls |grep domid
     domid = "11"

Zooming in libxl__xs_read, I got as far as :

libxl__xs_read -> xs_read((gc=0x636880, t=0x0, path=0x7ffff7bc13ba "domid")
 --> .. --> xs_talkv() where:

        ret = read_reply(h, &msg.type, len);
        if (!ret)
                goto fail;

        mutex_unlock(&h->request_mutex);

        sigaction(SIGPIPE, &oldact, NULL);
        if (msg.type == XS_ERROR) {
                saved_errno = get_error(ret); <=========

Ian(s), any thoughts/ideas?

thanks
mukesh