From mboxrd@z Thu Jan 1 00:00:00 1970 From: Amos Kong Subject: Re: [PATCH] virtio-rng: complete have_data completion in removing device Date: Wed, 6 Aug 2014 16:05:41 +0800 Message-ID: <20140806080541.GA3304@z.redhat.com> References: <1407260115-26767-1-git-send-email-akong@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1407260115-26767-1-git-send-email-akong@redhat.com> 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@lists.linux-foundation.org Cc: amit.shah@redhat.com, kvm@vger.kernel.org, stable@vger.kernel.org List-Id: virtualization@lists.linuxfoundation.org On Wed, Aug 06, 2014 at 01:35:15AM +0800, Amos Kong wrote: > When we try to hot-remove a busy virtio-rng device from QEMU monitor, > the device can't be hot-removed. Because virtio-rng driver hangs at > wait_for_completion_killable(). > > This patch fixed the hang by completing have_data completion before > unregistering a virtio-rng device. Hi Amit, Before applying this patch, it's blocking insider wait_for_completion_killable() Applied this patch, wait_for_completion_killable() returns 0, and vi->data_avail becomes 0, then rng_get_date() will return 0. Is it expected result? > Signed-off-by: Amos Kong > Cc: stable@vger.kernel.org > --- > drivers/char/hw_random/virtio-rng.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c > index 0027137..416b15c 100644 > --- a/drivers/char/hw_random/virtio-rng.c > +++ b/drivers/char/hw_random/virtio-rng.c > @@ -137,6 +137,7 @@ static void remove_common(struct virtio_device *vdev) > struct virtrng_info *vi = vdev->priv; > > vdev->config->reset(vdev); > + complete(&vi->have_data); > vi->busy = false; > if (vi->hwrng_register_done) > hwrng_unregister(&vi->hwrng); > -- > 1.9.3 > > _______________________________________________ > Virtualization mailing list > Virtualization@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/virtualization -- Amos.