From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Hildenbrand Subject: [PATCH v1 1/3] virtio-balloon: Fix memory leak when unloading while hinting is in progress Date: Wed, 5 Feb 2020 17:34:00 +0100 Message-ID: <20200205163402.42627-2-david@redhat.com> References: <20200205163402.42627-1-david@redhat.com> Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20200205163402.42627-1-david@redhat.com> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, virtualization@lists.linux-foundation.org, David Hildenbrand , "Michael S. Tsirkin" , Jason Wang , Wei Wang , Liang Li List-Id: virtualization@lists.linuxfoundation.org When unloading the driver while hinting is in progress, we will not release the free page blocks back to MM, resulting in a memory leak. Fixes: 86a559787e6f ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT") Cc: "Michael S. Tsirkin" Cc: Jason Wang Cc: Wei Wang Cc: Liang Li Signed-off-by: David Hildenbrand --- drivers/virtio/virtio_balloon.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_ball= oon.c index 8e400ece9273..abef2306c899 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -968,6 +968,10 @@ static void remove_common(struct virtio_balloon *vb) leak_balloon(vb, vb->num_pages); update_balloon_size(vb); =20 + /* There might be free pages that are being reported: release them. */ + if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) + return_free_pages_to_mm(vb, ULONG_MAX); + /* Now we reset the device so we can clean up the queues. */ vb->vdev->config->reset(vb->vdev); =20 --=20 2.24.1