[PATCH 5.9 579/757] vdpa/mlx5: Setup driver only if VIRTIO_CONFIG_S_DRIVER_OK

[Greg Kroah-Hartman]

From: Eli Cohen <elic@xxxxxxxxxx>

[ Upstream commit 1897f0b618b0af0eb9dca709ab6bdf9ef1969ef7 ]

set_map() is used by mlx5 vdpa to create a memory region based on the
address map passed by the iotlb argument. If we get successive calls, we
will destroy the current memory region and build another one based on
the new address mapping. We also need to setup the hardware resources
since they depend on the memory region.

If these calls happen before DRIVER_OK, It means that driver VQs may
also not been setup and we may not create them yet. In this case we want
to avoid setting up the other resources and defer this till we get
DRIVER OK.

Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices")
Signed-off-by: Eli Cohen <elic@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20200908123346.GA169007@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/vdpa/mlx5/net/mlx5_vnet.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 5ca309473c03d..1fa6fcac82992 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -1658,6 +1658,9 @@ static int mlx5_vdpa_change_map(struct mlx5_vdpa_net *ndev, struct vhost_iotlb *
 	if (err)
 		goto err_mr;
 
+	if (!(ndev->mvdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
+		return 0;
+
 	restore_channels_info(ndev);
 	err = setup_driver(ndev);
 	if (err)
-- 
2.25.1