Re: [PATCH net-next v2 19/21] net: ravb: Do not set promiscuous mode if the interface is down

From: Sergey Shtylyov
Date: Wed Dec 20 2023 - 15:44:42 EST


On 12/17/23 5:02 PM, claudiu beznea wrote:

[...]
>>> From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
>>>
>>> Do not allow setting promiscuous mode if the interface is down. In case
>>> runtime PM is enabled, and while interface is down, the IP will be in reset
>>> mode (as for some platforms disabling/enabling the clocks will switch the
>>> IP to standby mode which will lead to losing registers' content).
>>
>> Register.
>> Have this issue actually occurred for you?
>>
>>> Commit prepares for the addition of runtime PM.
>>>
>>> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
>> [...]
>>
>>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
>>> index 1995cf7ff084..633346b6cd7c 100644
>>> --- a/drivers/net/ethernet/renesas/ravb_main.c
>>> +++ b/drivers/net/ethernet/renesas/ravb_main.c
>>> @@ -2164,6 +2164,9 @@ static void ravb_set_rx_mode(struct net_device *ndev)
>>> struct ravb_private *priv = netdev_priv(ndev);
>>> unsigned long flags;
>>>
>>> + if (!netif_running(ndev))
>>
>> Seems racy as well...
>
> It is also called with rtnl_mutex locked at least though __dev_change_flags().

I'm tired of chasing the call tree for you. :-)
Since I'm hoping we'll agree on the ndo_get_stats() case, it would
seem safer to use an is_opened flag here as well, like sh_eth.c does.

[...]

MBR, Sergey