Re: [PATCH 2/2] [RESEND] console: implement lockdep support forconsole_lock

[Peter Zijlstra]

On Mon, 2012-09-24 at 14:17 +0200, Peter Zijlstra wrote:
> On Tue, 2012-09-18 at 01:03 +0200, Daniel Vetter wrote:
> > - In the printk code there's a special trylock, only used to kick off
> >   the logbuffer printk'ing in console_unlock. But all that happens
> >   while lockdep is disable (since printk does a few other evil
> >   tricks). So no issue there, either. 
> 
> Not particularly evil, just plain broken.
> 
> See this series:
> 
>   http://marc.info/?l=linux-kernel&m=132446644123326&w=2
> 
> In particular see patches 1-4. The problem with lockdep is that lockdep
> uses printk and printk's recursion stuff is utterly broken.
> 
> Console drivers being on crack simply doesn't help :-) Note that I would
> never recommend drm/ksm to anybody who really cares about their console
> output.

Also, don't cross-post with a subscribe only list.
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