Subject: Re: [PATCH v2] tracing: devlink: Use static array for string in devlink_trap_report even

From: Ido Schimmel <[email-masked]>
Date: Wed, 13 Jul 2022 09:34:09 +0300

On Tue, Jul 12, 2022 at 06:58:20PM -0400, Steven Rostedt wrote:
> From: "Steven Rostedt (Google)" <[email-masked]>
> 
> The trace event devlink_trap_report uses the __dynamic_array() macro to
> determine the size of the input_dev_name field. This is because it needs
> to test the dev field for NULL, and will use "NULL" if it is. But it also
> has the size of the dynamic array as a fixed IFNAMSIZ bytes. This defeats
> the purpose of the dynamic array, as this will reserve that amount of
> bytes on the ring buffer, and to make matters worse, it will even save
> that size in the event as the event expects it to be dynamic (for which it
> is not).
> 
> Since IFNAMSIZ is just 16 bytes, just make it a static array and this will
> remove the meta data from the event that records the size.
> 
> Cc: Jakub Kicinski <[email-masked]>
> Cc: Leon Romanovsky <[email-masked]>
> Cc: Jiri Pirko <[email-masked]>
> Cc: "David S. Miller" <[email-masked]>
> Cc: Eric Dumazet <[email-masked]>
> Cc: Paolo Abeni <[email-masked]>
> Cc: [email-masked]
> Signed-off-by: Steven Rostedt (Google) <[email-masked]>

Reviewed-by: Ido Schimmel <[email-masked]>
Tested-by: Ido Schimmel <[email-masked]>