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Date: Thu, 25 Jan 2024 21:26:16 +0100
From: Andrew Lunn <andrew@lunn.ch>
To: Danielle Ratson <danieller@nvidia.com>
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Subject: Re: [RFC PATCH net-next 1/9] ethtool: Add ethtool operation to write
 to a transceiver module EEPROM
Message-ID: <9eecccb0-a875-4dbc-b88c-5b2aad838305@lunn.ch>
References: <20240122084530.32451-1-danieller@nvidia.com>
 <20240122084530.32451-2-danieller@nvidia.com>
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In-Reply-To: <20240122084530.32451-2-danieller@nvidia.com>

On Mon, Jan 22, 2024 at 10:45:22AM +0200, Danielle Ratson wrote:
> From: Ido Schimmel <idosch@nvidia.com>
> 
> Ethtool can already retrieve information from a transceiver module
> EEPROM by invoking the ethtool_ops::get_module_eeprom_by_page operation.
> Add a corresponding operation that allows ethtool to write to a
> transceiver module EEPROM.
> 
> The purpose of this operation is not to enable arbitrary read / write
> access, but to allow the kernel to write to specific addresses as part
> of transceiver module firmware flashing. In the future, more
> functionality can be implemented on top of these read / write
> operations.

My memory is dim, but i thought we decided that since the algorithm to
program these modules is defined in the standard, all we need to do is
pass the firmware blob, and have an in kernel implementation of the
algorithm. There is no need to have an arbitrary write blob to module,
which might, or might not be abused in the future.

Also, is the module functional while its firmware is being upgraded?
Do we need to enforce the link is down?

   Andrew