[PATCH] net/mlx5: fix crash when secondary queries dev info after primary exits

[Stephen Hemminger]

On Mon, 21 Jul 2025 03:38:51 -0400
Khadem Ullah <14pwcse1224 at uetpeshawar.edu.pk> wrote:

> When the primary process exits, the shared mlx5 state becomes
> unavailable to secondary processes. If a secondary process attempts
> to query device information (e.g., via testpmd), a NULL dereference
> may occur due to missing shared data.
> 
> This patch adds a check for shared context availability and fails
> gracefully while preventing a crash.
> 
> Fixes: e60fbd5b24fc ("mlx5: add device configure/start/stop")
> Cc: stable at dpdk.org
> 
> Signed-off-by: Khadem Ullah <14pwcse1224 at uetpeshawar.edu.pk>
> ---

NAK
As per other thread. Drivers need not worry about this.
If secondary gets to this point it is using freed bus and device information
and nothing is valid.