From: Ido Schimmel <ido...@nvidia.com>
With the ioctl interface, when autoneg is enabled, but without
specifying speed, duplex or link modes, the advertised link modes are
set to the supported link modes by the ethtool user space utility.
Example:
# ethtool --version
ethtool version 5.4
# ethtool -s swp3 speed 100000 autoneg off
# ethtool swp3
Settings for swp3:
Supported ports: [ FIBRE ]
Supported link modes: 1000baseKX/Full
10000baseKR/Full
40000baseCR4/Full
40000baseSR4/Full
40000baseLR4/Full
25000baseCR/Full
25000baseSR/Full
50000baseCR2/Full
100000baseSR4/Full
100000baseCR4/Full
100000baseLR4_ER4/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: Not reported
Advertised pause frame use: No
Advertised auto-negotiation: No
Advertised FEC modes: Not reported
Speed: 100000Mb/s
Duplex: Full
Port: Direct Attach Copper
PHYAD: 0
Transceiver: internal
Auto-negotiation: off
Link detected: yes
# ethtool -s swp3 autoneg on
# ethtool swp3
Settings for swp3:
Supported ports: [ FIBRE ]
Supported link modes: 1000baseKX/Full
10000baseKR/Full
40000baseCR4/Full
40000baseSR4/Full
40000baseLR4/Full
25000baseCR/Full
25000baseSR/Full
50000baseCR2/Full
100000baseSR4/Full
100000baseCR4/Full
100000baseLR4_ER4/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 1000baseKX/Full
10000baseKR/Full
40000baseCR4/Full
40000baseSR4/Full
40000baseLR4/Full
25000baseCR/Full
25000baseSR/Full
50000baseCR2/Full
100000baseSR4/Full
100000baseCR4/Full
100000baseLR4_ER4/Full
Advertised pause frame use: No
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Speed: 100000Mb/s
Duplex: Full
Port: Direct Attach Copper
PHYAD: 0
Transceiver: internal
Auto-negotiation: on
Link detected: yes
With the netlink interface, the same thing is done by the kernel, but
only if speed or duplex are specified. In which case, the advertised
link modes are set by traversing the supported link modes and picking
the ones matching the specified speed or duplex.
However, if speed nor duplex are specified, the driver is passed an
empty advertised link modes bitmap. This causes the mlxsw driver to
return an error. Other drivers might also be affected. Example:
# ethtool --version
ethtool version 5.8
# ethtool -s swp3 speed 100000 autoneg off
# ethtool swp3
Settings for swp3:
Supported ports: [ FIBRE ]
Supported link modes: 1000baseKX/Full
10000baseKR/Full
40000baseCR4/Full
40000baseSR4/Full
40000baseLR4/Full
25000baseCR/Full
25000baseSR/Full
50000baseCR2/Full
100000baseSR4/Full
100000baseCR4/Full
100000baseLR4_ER4/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: Not reported
Advertised pause frame use: No
Advertised auto-negotiation: No
Advertised FEC modes: Not reported
Speed: 100000Mb/s
Duplex: Full
Auto-negotiation: off
Port: Direct Attach Copper
PHYAD: 0
Transceiver: internal
Link detected: yes
# ethtool -s swp3 autoneg on
netlink error: link settings update failed
netlink error: Invalid argument
Fix this incompatibility problem by having the kernel set the advertised
link modes according to the supported link modes even if speed nor
duplex are specified. In which case, the advertised link modes are set
to the supported link modes. Example after this patch:
# ethtool --version
ethtool version 5.8
# ethtool -s swp3 speed 100000 autoneg off
# ethtool swp3
Settings for swp3:
Supported ports: [ FIBRE ]
Supported link modes: 1000baseKX/Full
10000baseKR/Full
40000baseCR4/Full
40000baseSR4/Full
40000baseLR4/Full
25000baseCR/Full
25000baseSR/Full
50000baseCR2/Full
100000baseSR4/Full
100000baseCR4/Full
100000baseLR4_ER4/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: Not reported
Advertised pause frame use: No
Advertised auto-negotiation: No
Advertised FEC modes: Not reported
Speed: 100000Mb/s
Duplex: Full
Auto-negotiation: off
Port: Direct Attach Copper
PHYAD: 0
Transceiver: internal
Link detected: yes
# ethtool -s swp3 autoneg on
# ethtool swp3
Settings for swp3:
Supported ports: [ FIBRE ]
Supported link modes: 1000baseKX/Full
10000baseKR/Full
40000baseCR4/Full
40000baseSR4/Full
40000baseLR4/Full
25000baseCR/Full
25000baseSR/Full
50000baseCR2/Full
100000baseSR4/Full
100000baseCR4/Full
100000baseLR4_ER4/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 1000baseKX/Full
10000baseKR/Full
40000baseCR4/Full
40000baseSR4/Full
40000baseLR4/Full
25000baseCR/Full
25000baseSR/Full
50000baseCR2/Full
100000baseSR4/Full
100000baseCR4/Full
100000baseLR4_ER4/Full
Advertised pause frame use: No
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Speed: 100000Mb/s
Duplex: Full
Auto-negotiation: on
Port: Direct Attach Copper
PHYAD: 0
Transceiver: internal
Link detected: yes
Fixes: bfbcfe2032e7 ("ethtool: set link modes related data with LINKMODES_SET
request")
Signed-off-by: Ido Schimmel <ido...@nvidia.com>
---
Sending as RFC as this patch has yet to be tested in our regression
---
net/ethtool/linkmodes.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/net/ethtool/linkmodes.c b/net/ethtool/linkmodes.c
index 7044a2853886..a9458c76209e 100644
--- a/net/ethtool/linkmodes.c
+++ b/net/ethtool/linkmodes.c
@@ -288,9 +288,9 @@ linkmodes_set_policy[ETHTOOL_A_LINKMODES_MAX + 1] = {
};
/* Set advertised link modes to all supported modes matching requested speed
- * and duplex values. Called when autonegotiation is on, speed or duplex is
- * requested but no link mode change. This is done in userspace with ioctl()
- * interface, move it into kernel for netlink.
+ * and duplex values, if specified. Called when autonegotiation is on, but no
+ * link mode change. This is done in userspace with ioctl() interface, move it
+ * into kernel for netlink.
* Returns true if advertised modes bitmap was modified.
*/
static bool ethnl_auto_linkmodes(struct ethtool_link_ksettings *ksettings,
@@ -381,7 +381,6 @@ static int ethnl_update_linkmodes(struct genl_info *info,
struct nlattr **tb,
ethnl_update_u8(&lsettings->master_slave_cfg, master_slave_cfg, mod);
if (!tb[ETHTOOL_A_LINKMODES_OURS] && lsettings->autoneg &&
- (req_speed || req_duplex) &&
ethnl_auto_linkmodes(ksettings, req_speed, req_duplex))
*mod = true;
--
2.26.2
