On Thu Feb 16 2023, Vladimir Oltean wrote:
> taprio_calculate_gate_durations() depends on netdev_get_num_tc() and
> this returns 0. So it calculates the maximum gate durations for no
> traffic class.
>
> I had tested the blamed commit only with another patch in my tree, one
> which in the end I decided isn't valuable enough to submit ("net/sched:
> taprio: mask off bits in gate mask that exceed number of TCs").
>
> The problem is that having this patch threw off my testing. By moving
> the netdev_set_num_tc() call earlier, we implicitly gave to
> taprio_calculate_gate_durations() the information it needed.
>
> Extract only the portion from the unsubmitted change which applies the
> mqprio configuration to the netdev earlier.
>
> Link: https://patchwork.kernel.org/project/netdevbpf/patch/20230130173145.475943-15-vladimir.oltean@nxp.com/
> Fixes: a306a90c8ffe ("net/sched: taprio: calculate tc gate durations")
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>

Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>