RE: [EXTERNAL] Re: [net-next, v3] net: mana: Support HW link state events

[Haiyang Zhang]

> -----Original Message-----
> From: Paolo Abeni <pabeni@xxxxxxxxxx>
> Sent: Tuesday, October 28, 2025 10:31 AM
> To: Haiyang Zhang <haiyangz@xxxxxxxxxxxxxxxxxxx>; linux-
> hyperv@xxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx
> Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>; Paul Rosswurm
> <paulros@xxxxxxxxxxxxx>; Dexuan Cui <DECUI@xxxxxxxxxxxxx>; KY Srinivasan
> <kys@xxxxxxxxxxxxx>; wei.liu@xxxxxxxxxx; edumazet@xxxxxxxxxx;
> davem@xxxxxxxxxxxxx; kuba@xxxxxxxxxx; Long Li <longli@xxxxxxxxxxxxx>;
> ssengar@xxxxxxxxxxxxxxxxxxx; ernis@xxxxxxxxxxxxxxxxxxx;
> dipayanroy@xxxxxxxxxxxxxxxxxxx; Konstantin Taranov
> <kotaranov@xxxxxxxxxxxxx>; horms@xxxxxxxxxx;
> shradhagupta@xxxxxxxxxxxxxxxxxxx; leon@xxxxxxxxxx; mlevitsk@xxxxxxxxxx;
> yury.norov@xxxxxxxxx; Shiraz Saleem <shirazsaleem@xxxxxxxxxxxxx>;
> andrew+netdev@xxxxxxx; linux-rdma@xxxxxxxxxxxxxxx; linux-
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> Subject: [EXTERNAL] Re: [net-next, v3] net: mana: Support HW link state
> events
> 
> On 10/24/25 3:41 AM, Haiyang Zhang wrote:
> > @@ -3243,6 +3278,8 @@ static int mana_probe_port(struct mana_context
> *ac, int port_idx,
> >  		goto free_indir;
> >  	}
> >
> > +	netif_carrier_on(ndev);
> 
> Why is  the above needed? I thought mana_link_state_handle() should kick
> and set the carrier on as needed???

Thanks for the question -- our MANA NIC only sends out the link state down/up 
messages when need to let the VM rerun DHCP client and change IP address...

So, I need to add netif_carrier_on(ndev) in the probe(), otherwise the 
/sys/class/net/ethX/operstate will remain "unknown" until it receives the 
Link down/up messages which do NOT always happen.

Cc: @Paul Rosswurm

- Haiyang