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Date: Wed, 1 May 2024 07:37:58 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Ido Schimmel <idosch@nvidia.com>
Cc: Danielle Ratson <danieller@nvidia.com>, "netdev@vger.kernel.org"
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Subject: Re: [PATCH net-next v5 04/10] ethtool: Add flashing transceiver
 modules' firmware notifications ability
Message-ID: <20240501073758.3da76601@kernel.org>
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On Wed, 1 May 2024 10:53:48 +0300 Ido Schimmel wrote:
> We can try to use unicast, but the current design is influenced by
> devlink firmware flash (see __devlink_flash_update_notify()) and ethtool
> cable testing (see ethnl_cable_test_started() and
> ethnl_cable_test_finished()), both of which use multicast notifications
> although the latter does not update about progress.
> 
> Do you want us to try the unicast approach or be consistent with the
> above examples?

We are charting a bit of a new territory here, you're right that 
the precedents point in the direction of multicast.
The unicast is harder to get done on the kernel side (we should
probably also check that the socket pid didn't get reused, stop
sending the notifications when original socket gets closed?)
It will require using pretty much all the pieces of advanced
netlink infra we have, I'm happy to explain more, but I'll also
understand if you prefer to stick to multicast.