Re: [PATCH] Revert "cfg80211: make WEXT compatibility unselectable"

Arend van Spriel
2014-12-31T22:30:25Z

On 12/31/14 22:44, Theodore Ts'o wrote:
> On Wed, Dec 31, 2014 at 09:32:13PM +0100, Arend van Spriel wrote:
>>
>> Agree. I can't even recall using "ip" ever. iw help system does provide
>> command specific help. The phy keyword is both a command and a selector key,
>> which I realize is confusing to the user, eg. 'iw help info' does provide
>> help for the 'info' subcommand.
>
> Yeah, the confusing part is that "ip" tends to use "verb object"
> scheme, which is consistent with the Cisco IOS command set it was
> trying to emulate. So for ip, you do something like
>
> ip link info eth0
>
> Where as for "iw" it's almost exactly backwards, i.e.:
>
> iw wlan0 info
>
> It's actually rather unfortunate that there is no consistency between
> many of these tools, for example:
>
> ethtool --show-features eth0
>
> If we were going to create a new interface, wouldn't be nice if we
> could have some kind of consistency? Sigh; oh well, water under the
> bridge at this point.

And on that water there are different ships with different captains ;-)

>> Thanks. If there are still drivers, upstream or out-of-tree, providing only
>> WEXT API this will not work unless iwconfig/iwlist can distinguish those
>> from cfg80211-based drivers (which is possible) and fallback to WEXT ioctl
>> syscalls. Just not sure if it is worth the effort. As you stated below, it
>> does not seem "evil" to retain WEXT if that is providing users what they
>> need.
>
> Is it really that much effort? Unless there is some license
> incompatibility nonsense (i.e., GPLv2 vs GPLv3), the code's already
> there in the wireless-tools source. It would just be a matter of
> trying the new ioctls first, and then falling back to the WEXT ones if
> needed, right?

I don't think it is much effort. I think the nl80211 netlink api is not
an ioctl, but yeah it seems trivial. But if WEXT needs to stay for
people using WEXT-only drivers, it may be fine to keep cfg80211 wext
compatibility in place.

Regards,
Arend

> Cheers,
>
> - Ted