Re: [PATCH net-next] devlink: Require devlink lock during device reload

From: Jiri Pirko
Date: Mon Nov 01 2021 - 11:03:14 EST


Sun, Oct 31, 2021 at 06:35:56PM CET, leon@xxxxxxxxxx wrote:
>From: Leon Romanovsky <leonro@xxxxxxxxxx>
>
>Devlink reload was implemented as a special command which does _SET_
>operation, but doesn't take devlink->lock, while recursive devlink
>calls that were part of .reload_up()/.reload_down() sequence took it.
>
>This fragile flow was possible due to holding a big devlink lock
>(devlink_mutex), which effectively stopped all devlink activities,
>even unrelated to reloaded devlink.
>
>So let's make sure that devlink reload behaves as other commands and
>use special nested locking primitives with a depth of 1. Such change
>opens us to a venue of removing devlink_mutex completely, while keeping
>devlink locking complexity in devlink.c.
>
>Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx>

Looks fine to me.

Reviewed-by: Jiri Pirko <jiri@xxxxxxxxxx>