Le 23.05.2020 à 00:50, David Miller a écrit :

From: Valentin Longchamp <redacted>
Date: Wed, 20 May 2020 17:53:50 +0200

quoted

ugeth_quiesce/activate are used to halt the controller when there is a
link change that requires to reconfigure the mac.

The previous implementation called netif_device_detach(). This however
causes the initial activation of the netdevice to fail precisely because
it's detached. For details, see [1].

A possible workaround was the revert of commit
net: linkwatch: add check for netdevice being present to linkwatch_do_dev
However, the check introduced in the above commit is correct and shall be
kept.

The netif_device_detach() is thus replaced with
netif_tx_stop_all_queues() that prevents any tranmission. This allows to
perform mac config change required by the link change, without detaching
the corresponding netdevice and thus not preventing its initial
activation.

[1] https://lists.openwall.net/netdev/2020/01/08/201

Signed-off-by: Valentin Longchamp <redacted>
Acked-by: Matteo Ghidoni <redacted>

Applied, thanks.

Thanks David.

May I suggest that this get backported to stable until (including) the 
4.19 stable release ?

As the above mentioned commit, merged for 4.19,
124eee3f6955 net: linkwatch: add check for netdevice being present to 
linkwatch_do_dev
does indeed break the ucc_geth driver, this patch can be considered as a 
bugfix that should be taken into account for stable.