Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752011AbaKQJhV (ORCPT ); Mon, 17 Nov 2014 04:37:21 -0500 Received: from mx1.redhat.com ([209.132.183.28]:35150 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751679AbaKQJhU (ORCPT ); Mon, 17 Nov 2014 04:37:20 -0500 Date: Mon, 17 Nov 2014 11:37:01 +0200 From: "Michael S. Tsirkin" To: Jason Wang Cc: rusty@rustcorp.com.au, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Cornelia Huck , Wanlong Gao Subject: Re: [PATCH V3 1/2] virtio: introduce methods of sanitizing device features Message-ID: <20141117093701.GC20133@redhat.com> References: <1416215838-21700-1-git-send-email-jasowang@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1416215838-21700-1-git-send-email-jasowang@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 17, 2014 at 05:17:17PM +0800, Jason Wang wrote: > Buggy host may advertised buggy host features (a usual case is that host > advertise a feature whose dependencies were missed). In this case, driver > should detect and disable the buggy features by itself. > > This patch introduces driver specific sanitize_features() method which is > called just before features finalizing to detect and disable buggy features > advertised by host. > > Virtio-net will be the first user. > > Cc: Rusty Russell > Cc: Michael S. Tsirkin > Cc: Cornelia Huck > Cc: Wanlong Gao > Signed-off-by: Jason Wang Hmm this conflicts with virtio 1.0 work: we drop features as bitmap there. > --- > Changes from V2: > - fix typo > - rename fix_features to sanitize_features > --- > drivers/virtio/virtio.c | 4 ++++ > include/linux/virtio.h | 1 + > include/linux/virtio_config.h | 12 ++++++++++++ > 3 files changed, 17 insertions(+) > > diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c > index df598dd..6a86b4f 100644 > --- a/drivers/virtio/virtio.c > +++ b/drivers/virtio/virtio.c > @@ -181,6 +181,10 @@ static int virtio_dev_probe(struct device *_d) > if (device_features & (1 << i)) > set_bit(i, dev->features); > > + /* Sanitize buggy features advertised by host */ > + if (drv->sanitize_features) > + drv->sanitize_features(dev); > + > dev->config->finalize_features(dev); > > err = drv->probe(dev); > diff --git a/include/linux/virtio.h b/include/linux/virtio.h > index 65261a7..5aed283 100644 > --- a/include/linux/virtio.h > +++ b/include/linux/virtio.h > @@ -142,6 +142,7 @@ struct virtio_driver { > void (*scan)(struct virtio_device *dev); > void (*remove)(struct virtio_device *dev); > void (*config_changed)(struct virtio_device *dev); > + void (*sanitize_features)(struct virtio_device *dev); > #ifdef CONFIG_PM > int (*freeze)(struct virtio_device *dev); > int (*restore)(struct virtio_device *dev); > diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h > index 7f4ef66..7bd89ea 100644 > --- a/include/linux/virtio_config.h > +++ b/include/linux/virtio_config.h > @@ -96,6 +96,18 @@ static inline bool virtio_has_feature(const struct virtio_device *vdev, > return test_bit(fbit, vdev->features); > } > > +static inline void virtio_disable_feature(struct virtio_device *vdev, > + unsigned int fbit) > +{ > + BUG_ON(fbit >= VIRTIO_TRANSPORT_F_START); > + BUG_ON(vdev->config->get_status(vdev) & > + ~(VIRTIO_CONFIG_S_ACKNOWLEDGE | VIRTIO_CONFIG_S_DRIVER)); > + > + virtio_check_driver_offered_feature(vdev, fbit); > + > + clear_bit(fbit, vdev->features); > +} > + > static inline > struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev, > vq_callback_t *c, const char *n) > -- > 1.9.1 -- 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/