batman-adv: Merge bugfixes from 2020.2

* Revert "disable ethtool link speed detection when auto negotiation off"

Signed-off-by: Sven Eckelmann <sven@narfation.org>

batman-adv/Makefile

@@ -10,7 +10,7 @@ include $(TOPDIR)/rules.mk
 PKG_NAME:=batman-adv
 
 PKG_VERSION:=2019.2
-PKG_RELEASE:=7
+PKG_RELEASE:=8
 PKG_HASH:=70c3f6a6cf88d2b25681a76768a52ed92d9fe992ba8e358368b6a8088757adc8
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz

batman-adv/patches/0020-batman-adv-Revert-disable-ethtool-link-speed-detecti.patch

@@ -0,0 +1,76 @@
+From: Sven Eckelmann <sven@narfation.org>
+Date: Mon, 25 Nov 2019 10:46:50 +0100
+Subject: batman-adv: Revert "disable ethtool link speed detection when auto negotiation off"
+
+The commit d60b8fc69ef2 ("batman-adv: disable ethtool link speed detection
+when auto negotiation off") disabled the usage of ethtool's link_ksetting
+when auto negotation was enabled due to invalid values when used with
+tun/tap virtual net_devices. According to the patch, automatic measurements
+should be used for these kind of interfaces.
+
+But there are major flaws with this argumentation:
+
+* automatic measurements are not implemented
+* auto negotiation has nothing to do with the validity of the retrieved
+  values
+
+The first point has to be fixed by a longer patch series. The "validity"
+part of the second point must be addressed in the same patch series by
+dropping the usage of ethtool's link_ksetting (thus always doing automatic
+measurements over ethernet).
+
+Drop the patch again to have more default values for various net_device
+types/configurations. The user can still overwrite them using the
+batadv_hardif's BATADV_ATTR_THROUGHPUT_OVERRIDE.
+
+Reported-by: Matthias Schiffer <mschiffer@universe-factory.net>
+Signed-off-by: Sven Eckelmann <sven@narfation.org>
+
+Origin: upstream, https://git.open-mesh.org/batman-adv.git/commit/6e860b3d5e4147bafcda32bf9b3e769926f232c5
+
+diff --git a/compat-include/linux/ethtool.h b/compat-include/linux/ethtool.h
+index e1f39c3377febbd650a75206aafa9ae3e807762a..8dcbe02c3decf941e892af70a0a67653b010e65e 100644
+--- a/compat-include/linux/ethtool.h
++++ b/compat-include/linux/ethtool.h
+@@ -21,7 +21,6 @@ struct batadv_ethtool_link_ksettings {
+ 	struct {
+ 		__u32	speed;
+ 		__u8	duplex;
+-		__u8	autoneg;
+ 	} base;
+ };
+ 
+@@ -42,7 +41,6 @@ batadv_ethtool_get_link_ksettings(struct net_device *dev,
+ 		return ret;
+ 
+ 	link_ksettings->base.duplex = cmd.duplex;
+-	link_ksettings->base.autoneg = cmd.autoneg;
+ 	link_ksettings->base.speed = ethtool_cmd_speed(&cmd);
+ 
+ 	return 0;
+diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c
+index 2614a9caee008539cc489b71dabdc36ac0ae3752..a39af0eefad313101812118181ec0376b21b79bb 100644
+--- a/net/batman-adv/bat_v_elp.c
++++ b/net/batman-adv/bat_v_elp.c
+@@ -120,20 +120,7 @@ static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
+ 	rtnl_lock();
+ 	ret = __ethtool_get_link_ksettings(hard_iface->net_dev, &link_settings);
+ 	rtnl_unlock();
+-
+-	/* Virtual interface drivers such as tun / tap interfaces, VLAN, etc
+-	 * tend to initialize the interface throughput with some value for the
+-	 * sake of having a throughput number to export via ethtool. This
+-	 * exported throughput leaves batman-adv to conclude the interface
+-	 * throughput is genuine (reflecting reality), thus no measurements
+-	 * are necessary.
+-	 *
+-	 * Based on the observation that those interface types also tend to set
+-	 * the link auto-negotiation to 'off', batman-adv shall check this
+-	 * setting to differentiate between genuine link throughput information
+-	 * and placeholders installed by virtual interfaces.
+-	 */
+-	if (ret == 0 && link_settings.base.autoneg == AUTONEG_ENABLE) {
++	if (ret == 0) {
+ 		/* link characteristics might change over time */
+ 		if (link_settings.base.duplex == DUPLEX_FULL)
+ 			hard_iface->bat_v.flags |= BATADV_FULL_DUPLEX;