[PATCH 5.16 0990/1039] vdpa/mlx5: Restore cur_num_vqs in case of failure in change_num_qps()

From: Greg Kroah-Hartman
Date: Mon Jan 24 2022 - 17:54:56 EST


From: Eli Cohen <elic@xxxxxxxxxx>

commit 37e07e705888e4c3502f204e9c6785c9c2d6d86a upstream.

Restore ndev->cur_num_vqs to the original value in case change_num_qps()
fails.

Fixes: 52893733f2c5 ("vdpa/mlx5: Add multiqueue support")
Reviewed-by: Si-Wei Liu<si-wei.liu@xxxxxxxxxx>
Acked-by: Jason Wang <jasowang@xxxxxxxxxx>
Signed-off-by: Eli Cohen <elic@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220105114646.577224-10-elic@xxxxxxxxxx
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/vdpa/mlx5/net/mlx5_vnet.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -1552,9 +1552,11 @@ static int change_num_qps(struct mlx5_vd
return 0;

clean_added:
- for (--i; i >= cur_qps; --i)
+ for (--i; i >= 2 * cur_qps; --i)
teardown_vq(ndev, &ndev->vqs[i]);

+ ndev->cur_num_vqs = 2 * cur_qps;
+
return err;
}