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From: Roland Dreier <rdreier@cisco.com>
To: corbet@lwn.net (Jonathan Corbet)
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
       Ingo Molnar <mingo@elte.hu>, Andrew Morton <akpm@linux-foundation.org>,
       Peter Zijlstra <a.p.zijlstra@chello.nl>,
       Thomas Gleixner <tglx@linutronix.de>,
       Alan Cox <alan@lxorguk.ukuu.org.uk>,
       Alexander Viro <viro@ftp.linux.org.uk>, linux-kernel@vger.kernel.org,
       Stephen Rothwell <sfr@canb.auug.org.au>
Subject: Re: [PATCH, RFC] Char dev BKL pushdown v2
References: <19108.1211229722@vena.lwn.net>
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Date: Mon, 19 May 2008 15:18:06 -0700
In-Reply-To: <19108.1211229722@vena.lwn.net> (Jonathan Corbet's message of
	"Mon, 19 May 2008 14:42:02 -0600")
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 > That's part of it, but, as Alan pointed out, there's more.  The BKL
 > currently protects open() calls against concurrency with other opens,
 > with ioctl(), and with driver initialization as well.  So it's a matter
 > of having one's locking and ordering act together in general.

Thanks.  Just to be super-explicit, ioctl() cannot be called on a given
file until the open() for that particular file has returned, right?

And the point about driver initialization is that open() can be called
as soon as the file operations are registered, even if the module_init
function has not returned?

Thanks,
  Roland