| Message ID | 1364518226-31372-1-git-send-email-nab@linux-iscsi.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Mar 29, 2013 at 12:50:26AM +0000, Nicholas A. Bellinger wrote: > From: Nicholas Bellinger <nab@linux-iscsi.org> > > This patch adds a VHOST_SCSI_FEATURES mask minus VIRTIO_RING_F_EVENT_IDX > so that vhost-scsi-pci userspace will strip this feature bit once > GET_FEATURES reports it as being unsupported on the host. > > This is to avoid a bug where ->handle_kicks() are missed when EVENT_IDX > is enabled by default in userspace code. > > (mst: Rename to VHOST_SCSI_FEATURES add comment) > > Cc: Michael S. Tsirkin <mst@redhat.com> > Cc: Asias He <asias@redhat.com> > Cc: Paolo Bonzini <pbonzini@redhat.com> > Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Reviewed-by: Asias He <asias@redhat.com> > --- > drivers/vhost/tcm_vhost.c | 13 +++++++++++-- > 1 files changed, 11 insertions(+), 2 deletions(-) > > diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c > index 0524267..4a68c1f 100644 > --- a/drivers/vhost/tcm_vhost.c > +++ b/drivers/vhost/tcm_vhost.c > @@ -60,6 +60,15 @@ enum { > VHOST_SCSI_VQ_IO = 2, > }; > > +/* > + * VIRTIO_RING_F_EVENT_IDX seems broken. Not sure the bug is in > + * kernel but disabling it helps. > + * TODO: debug and remove the workaround. > + */ > +enum { > + VHOST_SCSI_FEATURES = VHOST_FEATURES & (~VIRTIO_RING_F_EVENT_IDX) > +}; > + > #define VHOST_SCSI_MAX_TARGET 256 > #define VHOST_SCSI_MAX_VQ 128 > > @@ -981,7 +990,7 @@ static void vhost_scsi_flush(struct vhost_scsi *vs) > > static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features) > { > - if (features & ~VHOST_FEATURES) > + if (features & ~VHOST_SCSI_FEATURES) > return -EOPNOTSUPP; > > mutex_lock(&vs->dev.mutex); > @@ -1027,7 +1036,7 @@ static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl, > return -EFAULT; > return 0; > case VHOST_GET_FEATURES: > - features = VHOST_FEATURES; > + features = VHOST_SCSI_FEATURES; > if (copy_to_user(featurep, &features, sizeof features)) > return -EFAULT; > return 0; > -- > 1.7.2.5 >
diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c index 0524267..4a68c1f 100644 --- a/drivers/vhost/tcm_vhost.c +++ b/drivers/vhost/tcm_vhost.c @@ -60,6 +60,15 @@ enum { VHOST_SCSI_VQ_IO = 2, }; +/* + * VIRTIO_RING_F_EVENT_IDX seems broken. Not sure the bug is in + * kernel but disabling it helps. + * TODO: debug and remove the workaround. + */ +enum { + VHOST_SCSI_FEATURES = VHOST_FEATURES & (~VIRTIO_RING_F_EVENT_IDX) +}; + #define VHOST_SCSI_MAX_TARGET 256 #define VHOST_SCSI_MAX_VQ 128 @@ -981,7 +990,7 @@ static void vhost_scsi_flush(struct vhost_scsi *vs) static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features) { - if (features & ~VHOST_FEATURES) + if (features & ~VHOST_SCSI_FEATURES) return -EOPNOTSUPP; mutex_lock(&vs->dev.mutex); @@ -1027,7 +1036,7 @@ static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl, return -EFAULT; return 0; case VHOST_GET_FEATURES: - features = VHOST_FEATURES; + features = VHOST_SCSI_FEATURES; if (copy_to_user(featurep, &features, sizeof features)) return -EFAULT; return 0;