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Date: Wed, 23 Dec 2009 16:53:36 +0200
From: Dan Carpenter <error27@gmail.com>
To: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Matt Mackall <mpm@selenic.com>, linux-kernel@vger.kernel.org
Subject: Re: double unlock in rng_dev_read()
Message-ID: <20091223145336.GB23721@bicker>
Mail-Followup-To: Dan Carpenter <error27@gmail.com>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	Matt Mackall <mpm@selenic.com>, linux-kernel@vger.kernel.org
References: <20091223131552.GA17923@bicker> <20091223143658.GA30992@gondor.apana.org.au>
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On Wed, Dec 23, 2009 at 10:36:58PM +0800, Herbert Xu wrote:
> On Wed, Dec 23, 2009 at 03:15:52PM +0200, Dan Carpenter wrote:
> > It seems like we unlock rng_mutex twice (2.6.33-rc1).
> > 
> > drivers/char/hw_random/core.c
> >    151                  mutex_unlock(&rng_mutex);
> >    152
> >    153                  if (need_resched())
> >    154                          schedule_timeout_interruptible(1);
> >    155
> >    156                  if (signal_pending(current)) {
> >    157                          err = -ERESTARTSYS;
> >    158                          goto out;
> >    159                  }
> >    160          }
> >    161  out_unlock:
> >    162          mutex_unlock(&rng_mutex);
> 
> Hmm, are you sure you didn't mistake out for out_unlock? :)

No no.  I mean when size hits zero we are rng_mutex is unlocked.

regards,
dan carpenter

> -- 
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> Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
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