-----Original Message-----
From: Jakub Kicinski <kuba@kernel.org>
Sent: Tuesday, October 28, 2025 6:02 PM
To: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Paolo Abeni <pabeni@redhat.com>; Haiyang Zhang
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Subject: Re: [EXTERNAL] Re: [net-next, v3] net: mana: Support HW link
state events

On Tue, 28 Oct 2025 19:36:02 +0000 Haiyang Zhang wrote:

quoted

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Why is  the above needed? I thought mana_link_state_handle() should

kick

quoted

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and set the carrier on as needed???

Thanks for the question -- our MANA NIC only sends out the link state

down/up

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messages when need to let the VM rerun DHCP client and change IP

address...

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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

quoted

Link down/up messages which do NOT always happen.

Oh that makes the code make much more sense.
Please add this and more detail into the commit message.

Will do.

quoted

+			if (!netif_carrier_ok(ndev))
+				netif_carrier_on(ndev);

Testing carrier_ok() before calling carrier_on/off is entirely
pointless, please see the relevant implementations.

BTW I think the ac->link_event accesses are technically racy,
wrap them in READ_ONCE() / WRITE_ONCE() while you respin.
(Unless mana_hwc_init_event_handler() is somehow under rtnl_lock)

I will remove the netif_carrier_ok(), and add READ/WRITE_ONCE.

Thanks,
- Haiyang