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From: Alexandre Courbot <gnurou@gmail.com>
To: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Andreas Larsson <andreas@gaisler.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	"linux-gpio@vger.kernel.org" <linux-gpio@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	ldv-project@linuxtesting.org
Subject: Re: Deadlock in grgpio_irq_unmap()
Date: Mon, 17 Aug 2015 17:24:19 +0900	[thread overview]
Message-ID: <CAAVeFuKFZ3pyC--K3y57GQRkXyGGRmCLA2rLDbVBLNAXd53jnw@mail.gmail.com> (raw)
In-Reply-To: <1438532122-25368-1-git-send-email-khoroshilov@ispras.ru>

On Mon, Aug 3, 2015 at 1:15 AM, Alexey Khoroshilov
<khoroshilov@ispras.ru> wrote:
> Dear colleagus,
>
> grgpio_irq_unmap() code looks quite suspicious regarding usage of
> priv->bgc.lock spinlock.
>
> It locks the spinlock in line 310:
>         spin_lock_irqsave(&priv->bgc.lock, flags);
> and then it can call grgpio_set_imask() in line 317:
>         grgpio_set_imask(priv, i, 0);
>
> But grgpio_set_imask() unconditionally locks the spinlock by itself.

Indeed, this looks plain wrong. I have sent a fix that moves the
spinlock acquisition outside of grgpio_set_imask().

      reply	other threads:[~2015-08-17  8:24 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-08-02 16:15 Deadlock in grgpio_irq_unmap() Alexey Khoroshilov
2015-08-17  8:24 ` Alexandre Courbot [this message]

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