Re: [PATCH v2 -next] vdpa: mlx5: change Kconfig depends to fix build errors

[Jason Wang]

On 2020/9/18 上午3:45, Randy Dunlap wrote:
> From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
>
> drivers/vdpa/mlx5/ uses vhost_iotlb*() interfaces, so add a dependency
> on VHOST to eliminate build errors.
>
> ld: drivers/vdpa/mlx5/core/mr.o: in function `add_direct_chain':
> mr.c:(.text+0x106): undefined reference to `vhost_iotlb_itree_first'
> ld: mr.c:(.text+0x1cf): undefined reference to `vhost_iotlb_itree_next'
> ld: mr.c:(.text+0x30d): undefined reference to `vhost_iotlb_itree_first'
> ld: mr.c:(.text+0x3e8): undefined reference to `vhost_iotlb_itree_next'
> ld: drivers/vdpa/mlx5/core/mr.o: in function `_mlx5_vdpa_create_mr':
> mr.c:(.text+0x908): undefined reference to `vhost_iotlb_itree_first'
> ld: mr.c:(.text+0x9e6): undefined reference to `vhost_iotlb_itree_next'
> ld: drivers/vdpa/mlx5/core/mr.o: in function `mlx5_vdpa_handle_set_map':
> mr.c:(.text+0xf1d): undefined reference to `vhost_iotlb_itree_first'
>
> Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx>
> Cc: Jason Wang <jasowang@xxxxxxxxxx>
> Cc: virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
> Cc: Saeed Mahameed <saeedm@xxxxxxxxxx>
> Cc: Leon Romanovsky <leonro@xxxxxxxxxx>
> Cc: netdev@xxxxxxxxxxxxxxx
> ---
> v2: change from select to depends (Saeed)
>
>   drivers/vdpa/Kconfig |    2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> --- linux-next-20200917.orig/drivers/vdpa/Kconfig
> +++ linux-next-20200917/drivers/vdpa/Kconfig
> @@ -31,7 +31,7 @@ config IFCVF
>   
>   config MLX5_VDPA
>   	bool "MLX5 VDPA support library for ConnectX devices"
> -	depends on MLX5_CORE
> +	depends on VHOST && MLX5_CORE


It looks to me that depending on VHOST is too heavyweight.

I guess what it really needs is VHOST_IOTLB. So we can use select 
VHOST_IOTLB here.

Thanks


>   	default n
>   	help
>   	  Support library for Mellanox VDPA drivers. Provides code that is