Re: [PATCH net] net: tls: set MSG_SPLICE_PAGES consistently

[Tariq Toukan <ttoukan.linux@gmail.com>]

On 08/08/2023 21:09, Jakub Kicinski wrote:
> We used to change the flags for the last segment, because
> non-last segments had the MSG_SENDPAGE_NOTLAST flag set.
> That flag is no longer a thing so remove the setting.
> 
> Since flags most likely don't have MSG_SPLICE_PAGES set
> this avoids passing parts of the sg as splice and parts
> as non-splice. Before commit under Fixes we'd have called
> tcp_sendpage() which would add the MSG_SPLICE_PAGES.
> 
> Why this leads to trouble remains unclear but Tariq
> reports hitting the WARN_ON(!sendpage_ok()) due to
> page refcount of 0.
> 
> Fixes: e117dcfd646e ("tls: Inline do_tcp_sendpages()")
> Reported-by: Tariq Toukan <tariqt@nvidia.com>
> Link: https://lore.kernel.org/all/4c49176f-147a-4283-f1b1-32aac7b4b996@gmail.com/
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
> CC: borisp@nvidia.com
> CC: john.fastabend@gmail.com
> CC: dhowells@redhat.com
> ---
>   net/tls/tls_main.c | 3 ---
>   1 file changed, 3 deletions(-)
> 
> diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
> index 7dbb8cd8f809..f550c84f3408 100644
> --- a/net/tls/tls_main.c
> +++ b/net/tls/tls_main.c
> @@ -139,9 +139,6 @@ int tls_push_sg(struct sock *sk,
>   
>   	ctx->splicing_pages = true;
>   	while (1) {
> -		if (sg_is_last(sg))
> -			msg.msg_flags = flags;
> -
>   		/* is sending application-limited? */
>   		tcp_rate_check_app_limited(sk);
>   		p = sg_page(sg);


Thanks for your patch.
Tested-by: Tariq Toukan <tariqt@nvidia.com>