From: Jakub Kicinski <kuba@kernel.org>
To: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Paolo Abeni <pabeni@redhat.com>,
Haiyang Zhang <haiyangz@linux.microsoft.com>,
"linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>,
"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
Paul Rosswurm <paulros@microsoft.com>,
Dexuan Cui <DECUI@microsoft.com>,
KY Srinivasan <kys@microsoft.com>,
"wei.liu@kernel.org" <wei.liu@kernel.org>,
"edumazet@google.com" <edumazet@google.com>,
"davem@davemloft.net" <davem@davemloft.net>,
Long Li <longli@microsoft.com>,
"ssengar@linux.microsoft.com" <ssengar@linux.microsoft.com>,
"ernis@linux.microsoft.com" <ernis@linux.microsoft.com>,
"dipayanroy@linux.microsoft.com" <dipayanroy@linux.microsoft.com>,
Konstantin Taranov <kotaranov@microsoft.com>,
"horms@kernel.org" <horms@kernel.org>,
"shradhagupta@linux.microsoft.com"
<shradhagupta@linux.microsoft.com>,
"leon@kernel.org" <leon@kernel.org>,
"mlevitsk@redhat.com" <mlevitsk@redhat.com>,
"yury.norov@gmail.com" <yury.norov@gmail.com>,
Shiraz Saleem <shirazsaleem@microsoft.com>,
"andrew+netdev@lunn.ch" <andrew+netdev@lunn.ch>,
"linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [EXTERNAL] Re: [net-next, v3] net: mana: Support HW link state events
Date: Tue, 28 Oct 2025 15:01:51 -0700 [thread overview]
Message-ID: <20251028150151.3b3b7121@kernel.org> (raw)
In-Reply-To: <BY1PR21MB3870D5B860FB1F26932EB73ACAFDA@BY1PR21MB3870.namprd21.prod.outlook.com>
On Tue, 28 Oct 2025 19:36:02 +0000 Haiyang Zhang wrote:
> > 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.
Oh that makes the code make much more sense.
Please add this and more detail into the commit message.
> + 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)
--
pw-bot: cr
next prev parent reply other threads:[~2025-10-28 22:01 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-10-24 1:41 [net-next, v3] net: mana: Support HW link state events Haiyang Zhang
2025-10-28 14:31 ` Paolo Abeni
2025-10-28 19:36 ` [EXTERNAL] " Haiyang Zhang
2025-10-28 22:01 ` Jakub Kicinski [this message]
2025-10-29 13:20 ` Haiyang Zhang
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