Re: [PATCH net v4] phy: mscc: Fix timestamping for vsc8584

[Vadim Fedorenko]

On 18/08/2025 09:10, Horatiu Vultur wrote:
> There was a problem when we received frames and the frames were
> timestamped. The driver is configured to store the nanosecond part of
> the timestmap in the ptp reserved bits and it would take the second part
> by reading the LTC. The problem is that when reading the LTC we are in
> atomic context and to read the second part will go over mdio bus which
> might sleep, so we get an error.
> The fix consists in actually put all the frames in a queue and start the
> aux work and in that work to read the LTC and then calculate the full
> received time.
>
> Fixes: 7d272e63e0979d ("net: phy: mscc: timestamping and PHC support")
> Signed-off-by: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx>
>
> ---
> v3->v4:
> - remove empty line
>
> v2->v3:
> - make sure to flush the rx_skbs_list when the driver is removed
>
> v1->v2:
> - use sk_buff_head instead of a list_head and spinlock_t
> - stop allocating vsc8431_skb but put the timestamp in skb->cb

Reviewed-by: Vadim Fedorenko <vadim.fedorenko@xxxxxxxxx>