Messages in this thread | | | Date | Wed, 2 Jun 2021 11:57:57 +0300 | From | Eli Cohen <> | Subject | Re: [PATCH 2/3] vdpa/mlx5: Only return vq ready if vq is initialized |
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Please abandon this patch. I am sending instead a patch that resets ready after reset.
On Tue, Jun 01, 2021 at 01:03:36PM +0800, Jason Wang wrote: > > 在 2021/6/1 下午12:13, Eli Cohen 写道: > > On Tue, Jun 01, 2021 at 10:18:04AM +0800, Jason Wang wrote: > > > 在 2021/6/1 上午12:04, Eli Cohen 写道: > > > > Only return the value of the ready field if the VQ is initialized in > > > > which case the value of the field is valid. > > > > > > > > Failing to do so can result in virtio_vdpa failing to load if the device > > > > was previously used by vhost_vdpa and the old values are ready. > > > > virtio_vdpa expects to find VQs in "not ready" state. > > > > > > > > Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices") > > > > Signed-off-by: Eli Cohen <elic@nvidia.com> > > > > --- > > > > drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +- > > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > > > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > > index 02a05492204c..f6b680d2ab1c 100644 > > > > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > > @@ -1407,7 +1407,7 @@ static bool mlx5_vdpa_get_vq_ready(struct vdpa_device *vdev, u16 idx) > > > > struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev); > > > > struct mlx5_vdpa_virtqueue *mvq = &ndev->vqs[idx]; > > > > - return mvq->ready; > > > > + return mvq->initialized && mvq->ready; > > > > > > I think the more suitable fix is to reset mvq->ready during reset. The > > > vq_ready should follow the queue_enable semantic in virtio-pci: > > > > > > " > > > The device MUST present a 0 in queue_enable on reset. > > > " > > Thinking again, I think we should call set_vq_ready() from > > qemu/virtio_vdpa etc. after reset to explicitly set ready to false. > > > This is not what I read from the spec and how the current driver behave. > > And I don't see why we need to stick to 1 after the reset. > > > > > > The ready indication is not necessairily a reflection of the hardware > > queue: > > > > "Virtual queue ready bit > > Writing one (0x1) to this register notifies the device that it can > > execute requests from this virtual queue. Reading from this register > > returns the last value written to it. Both read and write accesses apply > > to the queue selected by writing to QueueSel." > > > My understanding that this applies if not reset in the middle. We can > clarify this in the spec if needed. > > Thanks > > > > > > > > > Thanks > > > > > > > > > > } > > > > static int mlx5_vdpa_set_vq_state(struct vdpa_device *vdev, u16 idx, >
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