From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jakub Kicinski <kubakici@wp.pl>
Subject: Re: [PATCH net-next 1/3] net: ethtool: add support for forward
 error correction modes
Date: Thu, 6 Jul 2017 16:27:49 -0700
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Cc: Casey Leedom <leedom@chelsio.com>,
        Dustin Byford <dustin@cumulusnetworks.com>,
        Roopa Prabhu <roopa@cumulusnetworks.com>,
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        "olson@cumulusnetworks.com" <olson@cumulusnetworks.com>,
        Manoj Malviya <manojmalviya@chelsio.com>,
        Santosh Rastapur <santosh@chelsio.com>,
        "yuval.mintz@qlogic.com" <yuval.mintz@qlogic.com>,
        "odedw@mellanox.com" <odedw@mellanox.com>,
        "ariela@mellanox.com" <ariela@mellanox.com>,
        "galp@mellanox.com" <galp@mellanox.com>,
        "jeffrey.t.kirsher@intel.com" <jeffrey.t.kirsher@intel.com>
To: Andrew Lunn <andrew@lunn.ch>
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On Fri, 7 Jul 2017 01:15:50 +0200, Andrew Lunn wrote:
> > Even this feels too extreme for me.  I think users would hate it.  They
> > did an ifup and swapped cables.  They expect the OS/Driver/Firmware
> > to continue trying to honor their ifup request.  
> 
> Lets take a look around at other subsystems....
> 
> What happens if you hot-unplug a SATA drive?
> An MMC card?
> A USB device?
> A PCIe card?
> A CPU?
> An SDRAM?
> 
> Do you know of any subsystem that tried to keep its configuration
> across a hot unplug/plug event? I suspect they all require user space
> to take some action to get the newly plugged hardware into operation.

That was exactly my thinking initially, but I'm not so sure anymore
because the layer to which configuration is applied does not reside on
the portion of HW which is hot swapped.  I'm very far from an expert on
the PHY layer stuff but modules start at the PMA layer?

If only IEEE defined for us what the behaviour should be :)