From: Marcin Slusarz <marcin.slusarz@gmail.com>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: LKML <linux-kernel@vger.kernel.org>,
Frans Pop <elendil@planet.nl>,
"Eric W. Biederman" <ebiederm@xmission.com>
Subject: Re: [PATCH] parport/ppdev: fix registration of sysctl entries
Date: Sun, 6 Jul 2008 17:07:02 +0200 [thread overview]
Message-ID: <20080706150608.GA5401@joi> (raw)
In-Reply-To: <20080706001148.GX28946@ZenIV.linux.org.uk>
On Sun, Jul 06, 2008 at 01:11:48AM +0100, Al Viro wrote:
> On Sun, Jul 06, 2008 at 12:51:48AM +0100, Al Viro wrote:
>
> > I don't believe that it's right. Note that if you *do* race there, you
> > are fucked regardless of sysctls - ppdev.c::register_device() racing
> > with itself will do tons of fun things all by itself (starting with two
> > threads allocating different pdev and both setting pp->pdev).
I wouldn't call it a race - BKL is protecting multiple ioctl calls, so we
won't ever claim the device from two different threads.
> BTW, with your patch you'll have 100% reproducible double registration if
> you do PPCLAIM/PPRELEASE/PPCLAIN on one file descriptor.
Yes, I didn't notice PPRELEASE ioctl (I thought releasing the device is
done during close()).
next prev parent reply other threads:[~2008-07-06 15:08 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-07-05 13:21 [PATCH] parport/ppdev: fix registration of sysctl entries Marcin Slusarz
2008-07-05 23:51 ` Al Viro
2008-07-06 0:11 ` Al Viro
2008-07-06 4:05 ` Al Viro
2008-07-06 6:49 ` Eric W. Biederman
2008-07-06 8:11 ` Al Viro
2008-07-06 9:25 ` Eric W. Biederman
2008-07-06 16:22 ` Eduard - Gabriel Munteanu
2008-07-06 16:08 ` Alan Cox
2008-07-06 17:00 ` Eduard - Gabriel Munteanu
2008-07-06 18:09 ` Alan Cox
2008-07-06 15:12 ` Marcin Slusarz
2008-07-06 15:07 ` Marcin Slusarz [this message]
2008-07-06 16:01 ` Arjan van de Ven
2008-07-06 20:35 ` Al Viro
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