nl80211 controlling operational state of the interface

[Krishna Chaitanya]

On Thu, Mar 15, 2018 at 5:03 PM, Krishna Chaitanya
<chaitanya.mgit at gmail.com> wrote:
>
> Hi,
>
> As per the kernel documentation @
> https://elixir.bootlin.com/linux/latest/source/Documentation/networking/operstates.txt
>
> "userspace applications should follow the procedure for controlling the
> operational state of the interface:
>
> -subscribe to RTMGRP_LINK
> -set IFLA_LINKMODE to 1 via RTM_SETLINK
> -query RTM_GETLINK once to get initial state
> -if initial flags are not (IFF_LOWER_UP && !IFF_DORMANT), wait until
>  netlink multicast signals this state"
>
> The case in question is, lets say if the driver is setting the
> interface state to
> DORMANT waiting on some event from chip, as per the above the
> wpa_supplicant/hostapd
> should wait for the kernel to send an UP event. But its not waiting,
> instead it sends commands to the driver even when it is in dormant
> state.
>
> Is this expected?
>
> netlink: Operstate: ifindex=13 linkmode=-1 (no change), operstate=5
> (IF_OPER_DORMANT)
> RTM_NEWLINK: ifi_index=13 ifname=wlp8s0f0 operstate=2 linkmode=1
> ifi_family=0 ifi_flags=0x21003 ([UP][DORMANT])
> wlp8s0f0: State: DISCONNECTED -> SCANNING
>
Any hints? Can Driver use dormant feature to block interface?