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Date: Thu, 15 Dec 2011 10:32:20 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>, "Ted Ts'o" <tytso@mit.edu>,
        Greg KH <greg@kroah.com>, linux-kernel <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@elte.hu>
Subject: Re: printk() vs tty_io
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> We probably could, I can have a closer look, but the main question is,
> are we going to commit to no wakeups from console implementations? That
> would mean removing the USB serial console support and other such stuff.

That's a non starter.

> [ Personally I think USB serial console is insane, if you really need
> something like that use the ehci-dbgp thing, that at least has a chance
> of working. ]

Sometimes USB serial console is the best you've got.

> If we're not going to commit to that (which would be valid choice given
> where we are), my printk efforts are pointless and I'll reconsider.

For lockdep spews do they need to be spewed synchronously - clearly it's
good if they can be but its possible that they could be buffered ?

Alan