mlx5 throws ASSERT_RTNL() warnings on timestamp config, because
it tries to update features. mlx5e_hwtstamp_set() calls
netdev_update_features().
I missed this while grepping the drivers because tsconfig goes
through ndo_hwtstamp_set/get, not ethtool ops, even tho the new
uAPI is in ethtool Netlink. We could add a dedicated opt out bit
for mlx5, but NDOs were not supposed to be part of the ethtool locking
conversion in the first place.
The mlx5 features update is related to the "compressed CQE" format
which lacks timestamp, apparently. See commit c0194e2d0e ("net/mlx5e:
Disable rxhash when CQE compress is enabled").
Fixes: f9a3e05114 ("net: ethtool: optionally skip rtnl_lock on Netlink path for SET ops")
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Kory Maincent <kory.maincent@bootlin.com>
Link: https://patch.msgid.link/20260611200355.2020663-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
f48cd5b47b