From: Artem Bityutskiy <dedekind1@gmail.com>
To: Richard Weinberger <richard@nod.at>
Cc: dwmw2@infradead.org, computersforpeace@gmail.com,
linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org,
stable@vger.kernel.org
Subject: Re: [PATCH] UBI: Fix possible deadlock in erase_worker()
Date: Wed, 17 Sep 2014 11:43:41 +0300 [thread overview]
Message-ID: <1410943421.28850.93.camel@sauron.fi.intel.com> (raw)
In-Reply-To: <541948E3.3080602@nod.at>
On Wed, 2014-09-17 at 10:40 +0200, Richard Weinberger wrote:
> /*
> * nested locking. NOTE: rwsems are not allowed to recurse
> * (which occurs if the same task tries to acquire the same
> * lock instance multiple times), but multiple locks of the
> * same lock class might be taken, if the order of the locks
> * is always the same. This ordering rule can be expressed
> * to lockdep via the _nested() APIs, but enumerating the
> * subclasses that are used. (If the nesting relationship is
> * static then another method for expressing nested locking is
> * the explicit definition of lock class keys and the use of
> * lockdep_set_class() at lock initialization time.
> * See Documentation/lockdep-design.txt for more details.)
> */
>
> In this case the same task is taking the same lock multiple times,
> which is not allowed according to rwsem.h.
Yes, this part was missed, thanks.
--
Best Regards,
Artem Bityutskiy
next prev parent reply other threads:[~2014-09-17 8:43 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-16 7:48 [PATCH] UBI: Fix possible deadlock in erase_worker() Richard Weinberger
2014-09-17 8:28 ` Artem Bityutskiy
2014-09-17 8:40 ` Richard Weinberger
2014-09-17 8:43 ` Artem Bityutskiy [this message]
2014-09-17 9:35 ` Artem Bityutskiy
2014-09-19 9:46 ` Richard Weinberger
2014-09-19 10:47 ` Artem Bityutskiy
2014-09-19 11:01 ` Richard Weinberger
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