Re: tty, vt: lockdep warnings

[Sasha Levin <sasha.levin@oracle.com>]

On 11/05/2012 12:59 PM, Alan Cox wrote:
> On Mon, 5 Nov 2012 12:26:43 -0500
> Sasha Levin <levinsasha928@gmail.com> wrote:
> 
>> Ping? Should I bisect it?
>>
>> On Fri, Oct 26, 2012 at 9:37 AM, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
>>> On Thu, 25 Oct 2012 15:37:43 -0400
>>> Sasha Levin <sasha.levin@oracle.com> wrote:
>>>
>>>> Hi all,
>>>>
>>>> While fuzzing with trinity inside a KVM tools (lkvm) guest running latest -next kernel,
>>>> I've stumbled on the following spew:
>>>
>>> Looks real enough but its not a tty/vt layer spew. This is all coming out
>>> of the core framebuffer code which doesn't seem to be able to decide what
>>> the locking rules at the invocation of fb_notifier_call_chain are.
>>>
>>> It might need some console layer tweaking to provide 'register console
>>> and I already hold the locks' or similar but that notifier needs some
>>> kind of sanity applying as well.
>>>
>>> Cc'ing the fbdev folks
> 
> I've cc'd the framebuffer folks. I can see why its occurring but I have
> no idea how they intend to fix it and I've not seen any replies.
> 
> Sorry but I've got enough other things on my plate right now without
> trying to deal with the locking brain damage that the fbdev layer is.
> 
> As far as I can tell the actual bug proper is years old.
> 
> Alan
> 

Ow, I figured it's something new since I've only now started seeing it in fuzz
tests, and it reproduces pretty much every time.


Thanks,
Sasha