On Mon, Nov 21, 2022 at 6:11 PM Stefano Garzarella <sgarz...@redhat.com> wrote: > > Commit 69e1c14aa2 ("virtio: core: vq reset feature negotation support") > enabled VIRTIO_F_RING_RESET by default for all virtio devices. > > This feature is not currently emulated by QEMU, so for vhost and > vhost-user devices we need to make sure it is supported by the offloaded > device emulation (in-kernel or in another process). > To do this we need to add VIRTIO_F_RING_RESET to the features bitmap > passed to vhost_get_features(). This way it will be masked if the device > does not support it. > > This issue was initially discovered with vhost-vsock and vhost-user-vsock, > and then also tested with vhost-user-rng which confirmed the same issue. > They fail when sending features through VHOST_SET_FEATURES ioctl or > VHOST_USER_SET_FEATURES message, since VIRTIO_F_RING_RESET is negotiated > by the guest (Linux >= v6.0), but not supported by the device. > > Fixes: 69e1c14aa2 ("virtio: core: vq reset feature negotation support") > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1318 > Signed-off-by: Stefano Garzarella <sgarz...@redhat.com>
Acked-by: Jason Wang <jasow...@redhat.com> > --- > > To prevent this problem in the future, perhaps we should provide a function > (e.g. vhost_device_get_features) where we go to mask all non-device-specific > features (e.g VIRTIO_F_*, VIRTIO_RING_F_*) that are not emulated by QEMU but > we expect them to be emulated by the vhost or vhost-user devices. Adding Eugenio, this might not be true if we want to use shadow virtqueue for emulating some features? Thanks > Then we can call it in all .get_features callbacks just before return the > features. > > What do you think? > > But maybe better to do that for the next release, I will send an RFC. > > Thanks, > Stefano > --- > hw/block/vhost-user-blk.c | 1 + > hw/net/vhost_net.c | 1 + > hw/scsi/vhost-scsi.c | 1 + > hw/scsi/vhost-user-scsi.c | 1 + > hw/virtio/vhost-user-fs.c | 1 + > hw/virtio/vhost-user-gpio.c | 1 + > hw/virtio/vhost-user-i2c.c | 1 + > hw/virtio/vhost-user-rng.c | 11 +++++++++-- > hw/virtio/vhost-vsock-common.c | 1 + > net/vhost-vdpa.c | 1 + > 10 files changed, 18 insertions(+), 2 deletions(-) > > diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c > index 16ad400889..0d5190accf 100644 > --- a/hw/block/vhost-user-blk.c > +++ b/hw/block/vhost-user-blk.c > @@ -52,6 +52,7 @@ static const int user_feature_bits[] = { > VIRTIO_F_NOTIFY_ON_EMPTY, > VIRTIO_F_RING_PACKED, > VIRTIO_F_IOMMU_PLATFORM, > + VIRTIO_F_RING_RESET, > VHOST_INVALID_FEATURE_BIT > }; > > diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c > index feda448878..26e4930676 100644 > --- a/hw/net/vhost_net.c > +++ b/hw/net/vhost_net.c > @@ -75,6 +75,7 @@ static const int user_feature_bits[] = { > VIRTIO_NET_F_MTU, > VIRTIO_F_IOMMU_PLATFORM, > VIRTIO_F_RING_PACKED, > + VIRTIO_F_RING_RESET, > VIRTIO_NET_F_RSS, > VIRTIO_NET_F_HASH_REPORT, > > diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c > index bdf337a7a2..6a0fd0dfb1 100644 > --- a/hw/scsi/vhost-scsi.c > +++ b/hw/scsi/vhost-scsi.c > @@ -38,6 +38,7 @@ static const int kernel_feature_bits[] = { > VIRTIO_RING_F_INDIRECT_DESC, > VIRTIO_RING_F_EVENT_IDX, > VIRTIO_SCSI_F_HOTPLUG, > + VIRTIO_F_RING_RESET, > VHOST_INVALID_FEATURE_BIT > }; > > diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c > index bc37317d55..b7a71a802c 100644 > --- a/hw/scsi/vhost-user-scsi.c > +++ b/hw/scsi/vhost-user-scsi.c > @@ -36,6 +36,7 @@ static const int user_feature_bits[] = { > VIRTIO_RING_F_INDIRECT_DESC, > VIRTIO_RING_F_EVENT_IDX, > VIRTIO_SCSI_F_HOTPLUG, > + VIRTIO_F_RING_RESET, > VHOST_INVALID_FEATURE_BIT > }; > > diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c > index 1c40f42045..dc4014cdef 100644 > --- a/hw/virtio/vhost-user-fs.c > +++ b/hw/virtio/vhost-user-fs.c > @@ -32,6 +32,7 @@ static const int user_feature_bits[] = { > VIRTIO_F_NOTIFY_ON_EMPTY, > VIRTIO_F_RING_PACKED, > VIRTIO_F_IOMMU_PLATFORM, > + VIRTIO_F_RING_RESET, > > VHOST_INVALID_FEATURE_BIT > }; > diff --git a/hw/virtio/vhost-user-gpio.c b/hw/virtio/vhost-user-gpio.c > index 677d1c7730..5851cb3bc9 100644 > --- a/hw/virtio/vhost-user-gpio.c > +++ b/hw/virtio/vhost-user-gpio.c > @@ -24,6 +24,7 @@ static const int feature_bits[] = { > VIRTIO_RING_F_INDIRECT_DESC, > VIRTIO_RING_F_EVENT_IDX, > VIRTIO_GPIO_F_IRQ, > + VIRTIO_F_RING_RESET, > VHOST_INVALID_FEATURE_BIT > }; > > diff --git a/hw/virtio/vhost-user-i2c.c b/hw/virtio/vhost-user-i2c.c > index 864eba695e..1c9f3d20dc 100644 > --- a/hw/virtio/vhost-user-i2c.c > +++ b/hw/virtio/vhost-user-i2c.c > @@ -16,6 +16,7 @@ > > static const int feature_bits[] = { > VIRTIO_I2C_F_ZERO_LENGTH_REQUEST, > + VIRTIO_F_RING_RESET, > VHOST_INVALID_FEATURE_BIT > }; > > diff --git a/hw/virtio/vhost-user-rng.c b/hw/virtio/vhost-user-rng.c > index 8b47287875..f9084cde58 100644 > --- a/hw/virtio/vhost-user-rng.c > +++ b/hw/virtio/vhost-user-rng.c > @@ -16,6 +16,11 @@ > #include "qemu/error-report.h" > #include "standard-headers/linux/virtio_ids.h" > > +static const int feature_bits[] = { > + VIRTIO_F_RING_RESET, > + VHOST_INVALID_FEATURE_BIT > +}; > + > static void vu_rng_start(VirtIODevice *vdev) > { > VHostUserRNG *rng = VHOST_USER_RNG(vdev); > @@ -106,8 +111,10 @@ static void vu_rng_set_status(VirtIODevice *vdev, > uint8_t status) > static uint64_t vu_rng_get_features(VirtIODevice *vdev, > uint64_t requested_features, Error > **errp) > { > - /* No feature bits used yet */ > - return requested_features; > + VHostUserRNG *rng = VHOST_USER_RNG(vdev); > + > + return vhost_get_features(&rng->vhost_dev, feature_bits, > + requested_features); > } > > static void vu_rng_handle_output(VirtIODevice *vdev, VirtQueue *vq) > diff --git a/hw/virtio/vhost-vsock-common.c b/hw/virtio/vhost-vsock-common.c > index 29b9ab4f72..a67a275de2 100644 > --- a/hw/virtio/vhost-vsock-common.c > +++ b/hw/virtio/vhost-vsock-common.c > @@ -21,6 +21,7 @@ > > const int feature_bits[] = { > VIRTIO_VSOCK_F_SEQPACKET, > + VIRTIO_F_RING_RESET, > VHOST_INVALID_FEATURE_BIT > }; > > diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c > index 6811089231..2b4b85d8f8 100644 > --- a/net/vhost-vdpa.c > +++ b/net/vhost-vdpa.c > @@ -69,6 +69,7 @@ const int vdpa_feature_bits[] = { > VIRTIO_NET_F_CTRL_VQ, > VIRTIO_F_IOMMU_PLATFORM, > VIRTIO_F_RING_PACKED, > + VIRTIO_F_RING_RESET, > VIRTIO_NET_F_RSS, > VIRTIO_NET_F_HASH_REPORT, > VIRTIO_NET_F_GUEST_ANNOUNCE, > -- > 2.38.1 >