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toucan

Member

Registered: 2013-08-26

Posts: 13

[SOLVED] Failed to create P2P Device interface

Attempting to connect to wifi on a fresh installation produces the following error.

$ wpa_supplicant -B -i wlp0s20f3 -c /etc/wpa_supplicant/wpa_supplicant.conf
Successfully initialized wpa_supplicant
nl80211: kernel reports: Attribute failed policy validation
Failed to create interface p2p-dev-wlp0s20f3 -22 (Invalid argument)
nl80211: Failed to create a P2P Device interface p2p-dev-wlp0s20f3
P2P: Failed to enable P2P Device interface

Some relevant information:

$ lspci | grep -i wireless
00:14.3 Network controller: Intel Corporation Cannon Point-LP CNVi [Wireless-AC] (rev 11)

wpa_supplicant.conf format:

network={
    ssid="<network name>"
    psk="<password>"
}

I've checked that I have no other instances of wpa_supplicant running: pgrep -i wpa outputs nothing.
Any help would be much appreciated.

Last edited by toucan (2019-05-19 18:51:59)

cowile

Member

Registered: 2019-05-01

Posts: 15

Re: [SOLVED] Failed to create P2P Device interface

Post the output of

ip link show

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The Linux motto is "Laugh in the face of danger." Oops, wrong one. "Do it yourself." Yes, that's it. -- Linus Torvalds

toucan

Member

Registered: 2013-08-26

Posts: 13

Re: [SOLVED] Failed to create P2P Device interface

Thank you for the response. Passing ifnames=0 parmeter seems to fix this for me.

grobber

Member

Registered: 2018-02-09

Posts: 29

Re: [SOLVED] Failed to create P2P Device interface

I ran across this too: it's one of the first few links a search engine will turn up upon searching for either

"nl80211: kernel reports: Attribute failed policy validation"

or

"P2P: Failed to enable P2P Device interface"

I figured it'd help those stumbling upon it to spell out that solution slightly: the kernel parameter is net.ifnames (not just ifnames). So adding net.ifnames=0 inside the quotes in the line

GRUB_CMDLINE_LINUX="<whatever>"

in /etc/default/grub and then running 'sudo update-grub' will do it (after a reboot).

I was able to get an internet connection via wpa_supplicant + dhcpcd this way, whereas before, when the P2P errors where popping up, I couldn't.

Edit:

I was still curious as to why this happens. This github issue seems to have cracked it.

Apparently there's a 15-character interface-name upper cap (kernel-imposed? it's somewhat unclear to me based on that discussion). Overly long network interface names trip up against this and crash wpa_supplicant, apparently.

Last edited by grobber (2019-12-12 23:01:59)