Comment 27 for bug 1841040

It is perhaps worth mentioning that there are only two patches to r8169 in this time frame:

commit 1bcf165ac6556dc55a596d524b8187d1ba7a8c7d
Author: Zhu Yanjun <email address hidden>
Date: Sun Mar 12 05:02:54 2017 -0400

    r8169: replace init_timer with setup_timer

    Replace init_timer with setup_timer to simplify the source code.

    Signed-off-by: Zhu Yanjun <email address hidden>
    Signed-off-by: David S. Miller <email address hidden>

commit 6fa1ba61520576cf1346c4ff09a056f2950cb3bf
Author: Philippe Reynes <email address hidden>
Date: Thu Feb 23 22:34:43 2017 +0100

    net: realtek: r8169: use new api ethtool_{get|set}_link_ksettings

    The ethtool api {get|set}_settings is deprecated.
    We move this driver to new api {get|set}_link_ksettings.

    As I don't have the hardware, I'd be very pleased if
    someone may test this patch.

    Signed-off-by: Philippe Reynes <email address hidden>
    Signed-off-by: David S. Miller <email address hidden>

The difficulty of reproducing indicates it may be a timing-related issue, and the failure to negotiate a link suggests that the second patch may also be involved.