On Mon, Apr 15, 2019 at 04:48:02PM +0200, Stefan Sperling wrote:
> ieee80211_media_change() will return ENETRESET if the interface is
> switched into 11a/b/g/n mode from any other mode.
> ifmedia_ioctl() considers this an error and reverts ifmedia's state
> to the previous setting, even though net80211 has actually succeeded.
> The result is that if_media and net80211 have conflicting ideas about the
> current media mode of the interface, which can be observed with ifconfig.
Diff makes sense to me. Currently we have some drivers with media_change
functions returning the errno from ieee80211_media_change (iwn, iwm) and some
just returning 0 at the end (run, rtwn, ral). The ones returning 0 are mostly
ignoring possible errors from x_init() so I'm leaning towards making them more
like iwn/m.
>
> The commands below were run while the interface is down.
> Note how 'ifconfig mode' needs to be run twice to get consistent results:
>
> # ifconfig iwm0 | grep media:
> media: IEEE802.11 autoselect
> # ifconfig iwm0 mode 11b
> # ifconfig iwm0 | grep media:
> media: IEEE802.11 autoselect (autoselect mode 11b)
> # ifconfig iwm0 mode 11b
> # ifconfig iwm0 | grep media:
> media: IEEE802.11 autoselect mode 11b
> # ifconfig iwm0 mode 11g
> # ifconfig iwm0 | grep media:
> media: IEEE802.11 autoselect mode 11b (autoselect mode 11g)
> # ifconfig iwm0 mode 11g
> # ifconfig iwm0 | grep media:
> media: IEEE802.11 autoselect mode 11g
>
> The diff below fixes this issue for me:
>
> # ifconfig iwm0 | grep media:
> media: IEEE802.11 autoselect
> # ifconfig iwm0 mode 11b
> # ifconfig iwm0 | grep media:
> media: IEEE802.11 autoselect mode 11b
> # ifconfig iwm0 mode 11g
> # ifconfig iwm0 | grep media:
> media: IEEE802.11 autoselect mode 11g
>
> OK?
>
> diff 23a4e4a1e8913390694e35727d2131b2938cb472 /usr/src
> blob - 5168b074cbdd5a95f9945134cdd47c0649ad76a1
> file + sys/net/if_media.c
> --- sys/net/if_media.c
> +++ sys/net/if_media.c
> @@ -277,7 +277,7 @@ ifmedia_ioctl(struct ifnet *ifp, struct ifreq *ifr, st
> ifm->ifm_cur = match;
> ifm->ifm_media = newmedia;
> error = (*ifm->ifm_change)(ifp);
> - if (error) {
> + if (error && error != ENETRESET) {
> ifm->ifm_cur = oldentry;
> ifm->ifm_media = oldmedia;
> }
>
