Re: [PATCH net v2 2/2] net: clarify SO_DEVMEM_DONTNEED behavior in documentation

[Stanislav Fomichev]

On 11/07, Mina Almasry wrote:
> Document new behavior when the number of frags passed is too big.
> 
> Signed-off-by: Mina Almasry <almasrymina@xxxxxxxxxx>
> ---
>  Documentation/networking/devmem.rst | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/Documentation/networking/devmem.rst b/Documentation/networking/devmem.rst
> index a55bf21f671c..d95363645331 100644
> --- a/Documentation/networking/devmem.rst
> +++ b/Documentation/networking/devmem.rst
> @@ -225,6 +225,15 @@ The user must ensure the tokens are returned to the kernel in a timely manner.
>  Failure to do so will exhaust the limited dmabuf that is bound to the RX queue
>  and will lead to packet drops.
>  
> +The user must pass no more than 128 tokens, with no more than 1024 total frags
> +among the token->token_count across all the tokens. If the user provides more
> +than 1024 frags, the kernel will free up to 1024 frags and return early.
> +
> +The kernel returns the number of actual frags freed. The number of frags freed
> +can be less than the tokens provided by the user in case of:
> +

[..]

> +(a) an internal kernel leak bug.

If you're gonna respin, might be worth mentioning that the dmesg
will contain a warning in case of a leak?