Re: [dpdk-stable] [PATCH] net/mlx5: fix the RETA update without stopping device

[Raslan Darawsheh <rasland@nvidia.com>]

Hi,

> -----Original Message-----
> From: Bing Zhao <bingz@nvidia.com>
> Sent: Friday, November 5, 2021 8:11 AM
> To: Slava Ovsiienko <viacheslavo@nvidia.com>; Matan Azrad
> <matan@nvidia.com>
> Cc: dev@dpdk.org; Raslan Darawsheh <rasland@nvidia.com>;
> stable@dpdk.org; Ori Kam <orika@nvidia.com>; NBU-Contact-N?lio
> Laranjeiro <nelio.laranjeiro@6wind.com>
> Subject: [PATCH] net/mlx5: fix the RETA update without stopping device
> 
> The global redirection table is used to create the default flow
> rules for the ingress traffic with the lowest priority. It is also
> used to create the default RSS rule in the destination table when
> there is a tunnel offload.
> 
> To update the RETA in-flight, there is no restriction in the ethdev
> API. In the previous implementation of mlx5, a port restart was
> needed to make the new configuration take effect.
> 
> The restart is heavy, e.g., all the queues will be released and
> reallocated, users' rules will be flushed. Since the restart is
> internal, there is a risk to crash the application when some change
> in the ethdev is introduced but no workaround is done in mlx5 PMD.
> 
> The users' rules, including the default miss rule for tunnul
> offload, should not be impacted by the RETA update. It is improper
> to flush all rules when updating RETA.
> 
> With this patch, only the default rules will be flushed and
> re-created with the new table configuration.
> 
> Fixes: 3f2fe392bd49 ("net/mlx5: fix crash during RETA update")
> Cc: nelio.laranjeiro@6wind.com
> Cc: stable@dpdk.org
> 
> Signed-off-by: Bing Zhao <bingz@nvidia.com>
> Acked-by: Viacheslav Ovsiienko <viacheslavo@nvidia.com>

Patch applied to next-net-mlx,

Kindest regards,
Raslan Darawsheh