Commit ad1cd785 authored by Jakub Kicinski's avatar Jakub Kicinski Committed by David S. Miller
Browse files

ethtool: fec: add note about reuse of reserved 



struct ethtool_fecparam::reserved can't be used in SET, because
ethtool user space doesn't zero-initialize the structure.
Make this clear.

Suggested-by: default avatarAndrew Lunn <andrew@lunn.ch>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent f59798b8

include/uapi/linux/ethtool.h

+4 −0
Original line number Diff line number Diff line
@@ -1382,6 +1382,10 @@ struct ethtool_per_queue_op { 
 * @fec: Bitmask of configured FEC modes.

 * @reserved: Reserved for future extensions, ignore on GET, write 0 for SET.

 *

 * Note that @reserved was never validated on input and ethtool user space

 * left it uninitialized when calling SET. Hence going forward it can only be

 * used to return a value to userspace with GET.

 *

 * FEC modes supported by the device can be read via %ETHTOOL_GLINKSETTINGS.

 * FEC settings are configured by link autonegotiation whenever it's enabled.

 * With autoneg on %ETHTOOL_GFECPARAM can be used to read the current mode.