Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755395AbaJJWwG (ORCPT ); Fri, 10 Oct 2014 18:52:06 -0400 Received: from mx1.redhat.com ([209.132.183.28]:6075 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751514AbaJJWwA (ORCPT ); Fri, 10 Oct 2014 18:52:00 -0400 From: Amos Kong To: stable@vger.kernel.org Cc: rusty@rustcorp.com.au, amit.shah@redhat.com, gregkh@linuxfoundation.org, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: [3.16 stable PATCH 2/2] virtio-rng: skip reading when we start to remove the device Date: Sat, 11 Oct 2014 06:51:49 +0800 Message-Id: <1412981509-30025-3-git-send-email-akong@redhat.com> In-Reply-To: <1412981509-30025-1-git-send-email-akong@redhat.com> References: <1412981509-30025-1-git-send-email-akong@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Before we really unregister the hwrng device, reading will get stuck if the virtio device is reset. We should return error for reading when we start to remove the device. Signed-off-by: Amos Kong Reviewed-by: Amit Shah Cc: stable@vger.kernel.org Signed-off-by: Rusty Russell (cherry picked from commit f49819560f53b7f3a596a8ea2e6764dc86695b62) Signed-off-by: Amos Kong --- drivers/char/hw_random/virtio-rng.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c index b50252c..cb1688a 100644 --- a/drivers/char/hw_random/virtio-rng.c +++ b/drivers/char/hw_random/virtio-rng.c @@ -37,6 +37,7 @@ struct virtrng_info { char name[25]; int index; bool hwrng_register_done; + bool hwrng_removed; }; @@ -69,6 +70,9 @@ static int virtio_read(struct hwrng *rng, void *buf, size_t size, bool wait) int ret; struct virtrng_info *vi = (struct virtrng_info *)rng->priv; + if (vi->hwrng_removed) + return -ENODEV; + if (!vi->busy) { vi->busy = true; init_completion(&vi->have_data); @@ -137,6 +141,7 @@ static void remove_common(struct virtio_device *vdev) { struct virtrng_info *vi = vdev->priv; + vi->hwrng_removed = true; vi->data_avail = 0; complete(&vi->have_data); vdev->config->reset(vdev); -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/