[dpdk-dev] [PATCH] doc: add Linux rawio capability requirement in mlx5 guide

[Thomas Monjalon]

+Cc mlx5 maintainers

About the title: "rawio" is not a word.
"raw IO" would be better.

01/04/2021 09:49, Eli Britstein:
> For an application to be able to create "transfer" rte_flows for mlx5

What is "tranfer" rule?

rte_flows does not exist. You probably mean rte_flow rule.

> devices, it should have cap_sys_rawio capability.
> Document it.
> 
> Fixes: f772cc424c45 ("doc: add required Linux capabilities in mlx5 guide")
> Cc: stable at dpdk.org
> 
> Signed-off-by: Eli Britstein <elibr at nvidia.com>
> Reviewed-by: Gaetan Rivet <gaetanr at nvidia.com>
[...]
>  In order to run as a non-root user,
> -some capabilities must be granted to the application::
> +some capabilities must be granted to the application, while others are

If you wish to show that all are not a must,
better to replace "must be granted" by "may be required".

> +optional for some use cases. Capabilities can be set for example using

Please start new sentence on next line.

> +the setcap utilitiy::

typo: utility

>  
> -   setcap cap_sys_admin,cap_net_admin,cap_net_raw,cap_ipc_lock+ep <dpdk-app>
> +   setcap cap_net_admin,cap_net_raw,cap_ipc_lock,cap_sys_admin,cap_sys_rawio+ep <dpdk-app>
>  
>  Below are the reasons of the need for each capability:
>  
> -``cap_sys_admin``
> -   When using physical addresses (PA mode), with Linux >= 4.0,
> -   for access to ``/proc/self/pagemap``.
> -
>  ``cap_net_admin``
>     For device configuration.
>  
> @@ -477,6 +475,14 @@ Below are the reasons of the need for each capability:
>  ``cap_ipc_lock``
>     For DMA memory pinning.
>  
> +``cap_sys_admin`` optional
> +   When using physical addresses (PA mode), with Linux >= 4.0,
> +   for access to ``/proc/self/pagemap``.
> +
> +``cap_sys_rawio`` optional
> +   For the application to be able to apply rte_flow flows in transfer
> +   mode.

"For the application" looks useless.
We don't apply "rte_flow flows" but "flow rules".
What is "transfer mode"? It is not mentioned elsewhere in this doc.
How this capability is related to dv_esw_en?
Do we need it in case of trusted VF?