Jason Wang
2014-Nov-13 05:24 UTC
[PATCH 1/2] virito: introduce methods of fixing device features
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 fix_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 <rusty at rustcorp.com.au> Cc: Michael S. Tsirkin <mst at redhat.com> Signed-off-by: Jason Wang <jasowang at redhat.com> --- 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..7001d6e 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); + /* Fix buggy features advertised by host */ + if (drv->fix_features) + drv->fix_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..9d01b54 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 (*fix_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
Jason Wang
2014-Nov-13 05:24 UTC
[PATCH 2/2] virtio-net: fix buggy features advertised by host
This patch tries to detect the possible buggy features advertised by host and fix them. One example is current booting virtio-net with only ctrl_vq disabled, qemu may still advertise many features which depends it. This will trigger several BUG()s in virtnet_send_command(). This patch utilizes the fix_features() method, and disable all features that depends on ctrl_vq if it was not advertised. This fixes the crash when booting with ctrl_vq=off. Cc: Rusty Russell <rusty at rustcorp.com.au> Cc: Michael S. Tsirkin <mst at redhat.com> Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/net/virtio_net.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index ec2a8b4..d6bb5fa 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1948,6 +1948,40 @@ static int virtnet_restore(struct virtio_device *vdev) } #endif +static void virtnet_fix_features(struct virtio_device *dev) +{ + if (!virtio_has_feature(dev, VIRTIO_NET_F_CTRL_VQ)) { + if (virtio_has_feature(dev, VIRTIO_NET_F_CTRL_RX)) { + pr_warning("Disable VIRTIO_NET_F_CTRL_RX since host " + "does not advertise VIRTIO_NET_F_CTRL_VQ"); + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_RX); + } + if (virtio_has_feature(dev, VIRTIO_NET_F_CTRL_VLAN)) { + pr_warning("Disable VIRTIO_NET_F_CTRL_VLAN since host " + "does not advertise VIRTIO_NET_F_CTRL_VQ"); + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_VLAN); + } + if (virtio_has_feature(dev, VIRTIO_NET_F_GUEST_ANNOUNCE)) { + pr_warning("Disable VIRTIO_NET_F_GUEST_ANNOUCE since " + "host does not advertise " + "VIRTIO_NET_F_CTRL_VQ"); + virtio_disable_feature(dev, + VIRTIO_NET_F_GUEST_ANNOUNCE); + } + if (virtio_has_feature(dev, VIRTIO_NET_F_MQ)) { + pr_warning("Disable VIRTIO_NET_F_MQ since host " + "does not advertise VIRTIO_NET_F_CTRL_VQ"); + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_VLAN); + } + if (virtio_has_feature(dev, VIRTIO_NET_F_CTRL_MAC_ADDR)) { + pr_warning("Disable VIRTIO_NET_F_CTRL_MAC_ADDR since " + "host does not advertise " + "VIRTIO_NET_F_CTRL_VQ"); + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_VLAN); + } + } +} + static struct virtio_device_id id_table[] = { { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID }, { 0 }, @@ -1975,6 +2009,7 @@ static struct virtio_driver virtio_net_driver = { .probe = virtnet_probe, .remove = virtnet_remove, .config_changed = virtnet_config_changed, + .fix_features = virtnet_fix_features, #ifdef CONFIG_PM_SLEEP .freeze = virtnet_freeze, .restore = virtnet_restore, -- 1.9.1
Jason Wang
2014-Nov-13 05:42 UTC
[PATCH 2/2] virtio-net: fix buggy features advertised by host
On 11/13/2014 01:24 PM, Jason Wang wrote:> This patch tries to detect the possible buggy features advertised by host > and fix them. One example is current booting virtio-net with only > ctrl_vq disabled, qemu may still advertise many features which depends > it. This will trigger several BUG()s in virtnet_send_command(). > > This patch utilizes the fix_features() method, and disable all features that > depends on ctrl_vq if it was not advertised. > > This fixes the crash when booting with ctrl_vq=off. > > Cc: Rusty Russell <rusty at rustcorp.com.au> > Cc: Michael S. Tsirkin <mst at redhat.com> > Signed-off-by: Jason Wang <jasowang at redhat.com> > --- > drivers/net/virtio_net.c | 35 +++++++++++++++++++++++++++++++++++ > 1 file changed, 35 insertions(+) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index ec2a8b4..d6bb5fa 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -1948,6 +1948,40 @@ static int virtnet_restore(struct virtio_device *vdev) > } > #endif > > +static void virtnet_fix_features(struct virtio_device *dev) > +{ > + if (!virtio_has_feature(dev, VIRTIO_NET_F_CTRL_VQ)) { > + if (virtio_has_feature(dev, VIRTIO_NET_F_CTRL_RX)) { > + pr_warning("Disable VIRTIO_NET_F_CTRL_RX since host " > + "does not advertise VIRTIO_NET_F_CTRL_VQ"); > + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_RX); > + } > + if (virtio_has_feature(dev, VIRTIO_NET_F_CTRL_VLAN)) { > + pr_warning("Disable VIRTIO_NET_F_CTRL_VLAN since host " > + "does not advertise VIRTIO_NET_F_CTRL_VQ"); > + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_VLAN); > + } > + if (virtio_has_feature(dev, VIRTIO_NET_F_GUEST_ANNOUNCE)) { > + pr_warning("Disable VIRTIO_NET_F_GUEST_ANNOUCE since " > + "host does not advertise " > + "VIRTIO_NET_F_CTRL_VQ"); > + virtio_disable_feature(dev, > + VIRTIO_NET_F_GUEST_ANNOUNCE); > + } > + if (virtio_has_feature(dev, VIRTIO_NET_F_MQ)) { > + pr_warning("Disable VIRTIO_NET_F_MQ since host " > + "does not advertise VIRTIO_NET_F_CTRL_VQ"); > + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_VLAN); > + } > + if (virtio_has_feature(dev, VIRTIO_NET_F_CTRL_MAC_ADDR)) { > + pr_warning("Disable VIRTIO_NET_F_CTRL_MAC_ADDR since " > + "host does not advertise " > + "VIRTIO_NET_F_CTRL_VQ"); > + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_VLAN);Oops, this looks like a cut-and-paste error. Will post V2.> + } > + } > +} > + > static struct virtio_device_id id_table[] = { > { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID }, > { 0 }, > @@ -1975,6 +2009,7 @@ static struct virtio_driver virtio_net_driver = { > .probe = virtnet_probe, > .remove = virtnet_remove, > .config_changed = virtnet_config_changed, > + .fix_features = virtnet_fix_features, > #ifdef CONFIG_PM_SLEEP > .freeze = virtnet_freeze, > .restore = virtnet_restore,
Possibly Parallel Threads
- [PATCH 1/2] virito: introduce methods of fixing device features
- [PATCH 1/2] virito: introduce methods of fixing device features
- [PATCH 1/2] virito: introduce methods of fixing device features
- [PATCH 2/2] virtio-net: fix buggy features advertised by host
- [PATCH 2/2] virtio-net: fix buggy features advertised by host