Re: kobject (ffff88003ffbb4b8): tried to init an initialized object, something is seriously wrong.

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Mon, Feb 06, 2012 at 10:29:56AM -0800, Greg KH wrote:
> On Mon, Feb 06, 2012 at 01:20:40PM -0500, Konrad Rzeszutek Wilk wrote:
> > On Fri, Feb 03, 2012 at 01:42:35PM -0800, Greg KH wrote:
> > > On Fri, Feb 03, 2012 at 01:39:49PM -0800, Greg KH wrote:
> > > > On Fri, Feb 03, 2012 at 03:59:53PM -0500, Konrad Rzeszutek Wilk wrote:
> > > > > Hey Greg,
> > > > > 
> > > > > With or without your previous patch (the one that added an cpu_device_release
> > > > > function) I am getting this in 3.3-rc2.  I did not get this in 3.2.
> > > > > 
> > > > > I added some extra printks to make sure that the handle_vcpu_hotplug_event
> > > > > code actually did call 'arch_unregister_cpu' which is certainly looks
> > > > > to be doing.
> > > > > 
> > > > > I hadn't done a bisection yet, but was wondering if this is related
> > > > > to the previous issues with the sysdev. Or kobject getting more observant.
> > > > 
> > > > No, it's related to the previous issue, let me knock up a patch to fix
> > > > this as well...
> > > 
> > > Does this patch solve the problem for you?
> > 
> > Yeah, no warnings. But neither is the CPU coming back up :-(
> 
> Very wierd.

Found the culprit and have a patch for it. But it does not affect baremetal and
it was in the drivers/xen/cpu_hotplug.c code - so 

> 
> > Thought that might be related to something else  - let me double check
> > with 3.2 whether there are some race-conditions that I might be hitting.
> 
> Ok, I'll wait to queue this up until you get back to me.

.. you can go ahead and queue it up with my Tested-by tag. Thanks!