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From: Paul Clements <paul.clements@steeleye.com>
To: Pavel Machek <pavel@suse.cz>
Cc: kernel list <linux-kernel@vger.kernel.org>,
	Andrew Morton <akpm@osdl.org>
Subject: Re: nbd: add locking to nbd_ioctl
Date: Fri, 16 Jan 2009 10:24:06 -0500	[thread overview]
Message-ID: <4970A696.9070307@steeleye.com> (raw)
In-Reply-To: <20090116115512.GA10771@elf.ucw.cz>

Pavel Machek wrote:
> The code was written with "oh big kernel lock, please protect me from
> all the evil" mentality: it does not locks its own data structures, it
> just hopes that big kernel lock somehow helps.
> 
> It does not. (My fault).
> 
> So this uses tx_lock to protect data structures from concurrent use
> between ioctl and worker threads.

What is the particular problem that this fixes? I thought we had already 
been careful to take tx_lock where necessary to protect data structures. 
   Perhaps there is something I missed?

--
Paul

  parent reply	other threads:[~2009-01-16 15:24 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-01-16 11:55 nbd: add locking to nbd_ioctl Pavel Machek
2009-01-16 12:08 ` Pavel Machek
2009-01-16 12:29 ` Arnd Bergmann
2009-01-16 15:24 ` Paul Clements [this message]
2009-01-16 15:36   ` Pavel Machek
2009-01-16 16:28     ` Paul Clements
2009-01-19  9:54       ` Pavel Machek
2009-01-19 14:56         ` Paul Clements
2009-01-26 16:49           ` Pavel Machek
2009-01-26 17:01             ` Paul Clements
2009-01-26 17:32               ` Pavel Machek
  -- strict thread matches above, loose matches on Subject: below --
2009-01-26 17:31 Pavel Machek
2009-01-29  1:14 ` Andrew Morton
2009-01-29  1:18 ` Andrew Morton

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