linux/net/ethtool
Andy Roulin e847c7675e ethtool: reset #lanes when lanes is omitted
If the number of lanes was forced and then subsequently the user
omits this parameter, the ksettings->lanes is reset. The driver
should then reset the number of lanes to the device's default
for the specified speed.

However, although the ksettings->lanes is set to 0, the mod variable
is not set to true to indicate the driver and userspace should be
notified of the changes.

The consequence is that the same ethtool operation will produce
different results based on the initial state.

If the initial state is:
$ ethtool swp1 | grep -A 3 'Speed: '
        Speed: 500000Mb/s
        Lanes: 2
        Duplex: Full
        Auto-negotiation: on

then executing 'ethtool -s swp1 speed 50000 autoneg off' will yield:
$ ethtool swp1 | grep -A 3 'Speed: '
        Speed: 500000Mb/s
        Lanes: 2
        Duplex: Full
        Auto-negotiation: off

While if the initial state is:
$ ethtool swp1 | grep -A 3 'Speed: '
        Speed: 500000Mb/s
        Lanes: 1
        Duplex: Full
        Auto-negotiation: off

executing the same 'ethtool -s swp1 speed 50000 autoneg off' results in:
$ ethtool swp1 | grep -A 3 'Speed: '
        Speed: 500000Mb/s
        Lanes: 1
        Duplex: Full
        Auto-negotiation: off

This patch fixes this behavior. Omitting lanes will always results in
the driver choosing the default lane width for the chosen speed. In this
scenario, regardless of the initial state, the end state will be, e.g.,

$ ethtool swp1 | grep -A 3 'Speed: '
        Speed: 500000Mb/s
        Lanes: 2
        Duplex: Full
        Auto-negotiation: off

Fixes: 012ce4dd31 ("ethtool: Extend link modes settings uAPI with lanes")
Signed-off-by: Andy Roulin <aroulin@nvidia.com>
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/ac238d6b-8726-8156-3810-6471291dbc7f@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-04 18:57:10 -07:00
..
bitset.c ethtool: fix stack overflow in ethnl_parse_bitset() 2020-12-09 15:50:38 -08:00
bitset.h ethtool: add ethnl_parse_bitset() helper 2020-03-12 15:32:32 -07:00
cabletest.c net: delete extra space and tab in blank line 2022-07-25 19:38:31 -07:00
channels.c ethtool: netlink: convert commands to common SET 2023-01-27 12:24:32 +00:00
coalesce.c ethtool: netlink: convert commands to common SET 2023-01-27 12:24:32 +00:00
common.c drivers/net/phy: add the link modes for the 10BASE-T1S Ethernet PHY 2023-01-11 08:35:02 +00:00
common.h net: ethtool: netlink: retrieve stats from multiple sources (eMAC, pMAC) 2023-01-23 12:44:18 +00:00
debug.c ethtool: netlink: convert commands to common SET 2023-01-27 12:24:32 +00:00
eee.c ethtool: netlink: convert commands to common SET 2023-01-27 12:24:32 +00:00
eeprom.c ethtool: eeprom: fix null-deref on genl_info in dump 2022-10-24 19:08:07 -07:00
features.c ethtool: use ethnl_parse_header_dev_put() 2021-12-15 10:27:47 +00:00
fec.c ethtool: netlink: convert commands to common SET 2023-01-27 12:24:32 +00:00
ioctl.c net/ethtool/ioctl: split ethtool_get_phy_stats into multiple helpers 2022-12-28 11:55:24 +00:00
linkinfo.c ethtool: netlink: convert commands to common SET 2023-01-27 12:24:32 +00:00
linkmodes.c ethtool: reset #lanes when lanes is omitted 2023-04-04 18:57:10 -07:00
linkstate.c ethtool: linkstate: add a statistic for PHY down events 2022-11-08 10:36:54 +01:00
Makefile net: ethtool: add support for MAC Merge layer 2023-01-23 12:44:18 +00:00
mm.c net: ethtool: fix __ethtool_dev_mm_supported() implementation 2023-02-21 09:05:01 -08:00
module.c ethtool: netlink: convert commands to common SET 2023-01-27 12:24:32 +00:00
netlink.c ethtool: netlink: convert commands to common SET 2023-01-27 12:24:32 +00:00
netlink.h net: ethtool: extend ringparam set/get APIs for rx_push 2023-02-13 11:05:12 +00:00
pause.c ethtool: netlink: handle SET intro/outro in the common code 2023-01-27 12:24:31 +00:00
phc_vclocks.c ethtool: add a new command for getting PHC virtual clocks 2021-07-01 13:08:18 -07:00
plca.c ethtool: netlink: convert commands to common SET 2023-01-27 12:24:32 +00:00
privflags.c ethtool: netlink: convert commands to common SET 2023-01-27 12:24:32 +00:00
pse-pd.c ethtool: pse-pd: Fix double word in comments 2023-02-21 09:02:13 -08:00
rings.c net: ethtool: extend ringparam set/get APIs for rx_push 2023-02-13 11:05:12 +00:00
rss.c ethtool: add netlink attr in rss get reply only if value is not null 2023-01-12 21:52:46 -08:00
stats.c net: ethtool: fix NULL pointer dereference in stats_prepare_data() 2023-01-25 09:56:31 +00:00
strset.c ethtool: strset: report missing ETHTOOL_A_STRINGSET_ID via ext_ack 2022-08-30 12:20:43 +02:00
tsinfo.c ethtool: link up ethnl_header_policy as a nested policy 2020-10-06 06:25:55 -07:00
tunnels.c ethtool: tunnels: check the return value of nla_nest_start() 2022-09-22 19:28:10 -07:00
wol.c ethtool: netlink: convert commands to common SET 2023-01-27 12:24:32 +00:00