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Date: Sat, 2 Jun 2012 21:00:06 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>, Alan Cox <alan@linux.intel.com>,
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        Jens Axboe <jaxboe@fusionio.com>
Subject: Re: [PATCH] tty: add lockdep annotations
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> 'tty_mutex' protect every tty_kref_put(). So I think we have two
> options:
> 
>  - revert all the tty locking changes
> 
>  - make a new global lock that protects just driver->ops->lookup(),
> driver->ttys[idx], and driver->ops->remove()

I've been working on the latter as a later step already. It triggers a
whole set of other horrible problems about synchronization between
driver->ttys[] and driver->termios.

Can we just punt the tty localisation patches for a release (the last
console one before it is fine). 

This isn't urgent stuff, its gradual cleaning the kernel up stuff and if
we keep it in -next for another cycle while fixing up these cases there
will be no hardware not supported, nobody unable to use their system, no
regressions. Better to get it right first because its ugly and
complicated as hell.

Alan