From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rusty Russell Subject: Re: [PATCH v3 7/9] virtio: console: add locking in port unplug path Date: Mon, 29 Jul 2013 14:24:22 +0930 Message-ID: <877gga6k5d.fsf@rustcorp.com.au> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Virtualization List Cc: Amit Shah List-Id: virtualization@lists.linuxfoundation.org Amit Shah writes: > Port unplug can race with close() in port_fops_release(). > port_fops_release() already takes the necessary locks, ensure > unplug_port() does that too. > > Signed-off-by: Amit Shah Applied, Rusty. > --- > drivers/char/virtio_console.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c > index 9cbed93..e8b707d 100644 > --- a/drivers/char/virtio_console.c > +++ b/drivers/char/virtio_console.c > @@ -1541,6 +1541,7 @@ static void unplug_port(struct port *port) > list_del(&port->list); > spin_unlock_irq(&port->portdev->ports_lock); > > + spin_lock_irq(&port->inbuf_lock); > if (port->guest_connected) { > /* Let the app know the port is going down. */ > send_sigio_to_port(port); > @@ -1551,6 +1552,7 @@ static void unplug_port(struct port *port) > > wake_up_interruptible(&port->waitqueue); > } > + spin_unlock_irq(&port->inbuf_lock); > > if (is_console_port(port)) { > spin_lock_irq(&pdrvdata_lock); > -- > 1.8.1.4