From: Breno Leitao

Sent: 25 January 2023 18:53
This patch removes the msleep(4s) during netpoll_setup() if the carrier
appears instantly.

Here are some scenarios where this workaround is counter-productive in
modern ages:

Servers which have BMC communicating over NC-SI via the same NIC as gets
used for netconsole. BMC will keep the PHY up, hence the carrier
appearing instantly.

The link is fibre, SERDES getting sync could happen within 0.1Hz, and
the carrier also appears instantly.

Other than that, if a driver is reporting instant carrier and then
losing it, this is probably a driver bug.

I can't help feeling that this will break something.
The 4 second delay does look counter productive though.
Obvious alternatives are 'wait a bit before the first check'
and 'require carrier to be present for a few checks'.

It also has to be said that checking every ms seems over enthusiastic.

	David

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