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Date:   Sun, 9 Apr 2023 12:02:24 +0300
From:   Leon Romanovsky <leon@kernel.org>
To:     Ivan Vecera <ivecera@redhat.com>
Cc:     netdev@vger.kernel.org, mschmidt@redhat.com,
        Michael Chan <michael.chan@broadcom.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH net-next] bnxt_en: Allow to set switchdev mode without
 existing VFs
Message-ID: <20230409090224.GE14869@unreal>
References: <20230406130455.1155362-1-ivecera@redhat.com>
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On Thu, Apr 06, 2023 at 03:04:55PM +0200, Ivan Vecera wrote:
> Remove an inability of bnxt_en driver to set eswitch to switchdev
> mode without existing VFs by:
> 
> 1. Allow to set switchdev mode in bnxt_dl_eswitch_mode_set() so
>    representors are created only when num_vfs > 0 otherwise just
>    set bp->eswitch_mode
> 2. Do not automatically change bp->eswitch_mode during
>    bnxt_vf_reps_create() and bnxt_vf_reps_destroy() calls so
>    the eswitch mode is managed only by an user by devlink.
>    Just set temporarily bp->eswitch_mode to legacy to avoid
>    re-opening of representors during destroy.
> 3. Create representors in bnxt_sriov_enable() if current eswitch
>    mode is switchdev one
> 
> Tested by this sequence:
> 1. Set PF interface up
> 2. Set PF's eswitch mode to switchdev
> 3. Created N VFs
> 4. Checked that N representors were created
> 5. Set eswitch mode to legacy
> 6. Checked that representors were deleted
> 7. Set eswitch mode back to switchdev
> 8. Checked that representros were re-created

Why do you think that this last item is the right behavior?
IMHO all configurations which were done after you switched mode
should be cleared and not recreated while toggling.

Thanks

> 9. Deleted all VFs
> 10. Checked that all representors were deleted as well
> 11. Checked that current eswitch mode is still switchdev
> 
> Signed-off-by: Ivan Vecera <ivecera@redhat.com>
> ---