On Sun, 2023-04-23 at 10:55 +0200, Uwe Kleine-König wrote: > Hello Gregory, > > there is a thread on debian-user-german@xxxxxxxxxxxxxxxx[1] about > broken wifi on Thinkpads when they are supposed to be connected to the > hotspots available in ICE4 trains. The mailing lists language is German > and the thread is long, so I sum up the problem: > > - It only affects the wifi equipment in ICE4 trains, the older ones work > fine. > > - Can be seen at least on > - Jürgen's laptop (Intel Corporation Wireless 8260 [8086:24f3] (rev 3a)) > - Marc's Thinkpad X260 (Intel Corporation Wireless 8260 [8086:24f3] (rev 3a)) > - Uwe's Thinkpad T460p (Intel Corporation Wireless 8260 [8086:24f3] (rev 3a)) > > - Other Thinkpads with a Realtek-Chip doesn't show the problem > > - Works on puppy-Linux with 4.19.23, however Debian with 4.19.0-18 is > also broken. > > - The OP provided a syslog dump at > https://lists.debian.org/msgid-search/75ad7ff2-ef25-90cd-2cb3-1f49f3e4909e@xxxxxxxxx > > I don't reproduce it here, but the gist seems to be: > > Jun 23 15:44:53 lina kernel: [ 1006.011129] wlp1s0: deauthenticated from 3c:51:0e:56:32:80 (Reason: 2=PREV_AUTH_NOT_VALID) > > - it seems to help to do: > $ cat /etc/modprobe.d/iwlwifi.conf > options iwlwifi 11n_disable=1 swcrypto=0 bt_coex_active=0 power_save=0 > options iwlmvm power_scheme=1 > options iwlwifi d0i3_disable=1 > options iwlwifi uapsd_disable=1 > options iwlwifi lar_disable=1 > > I added all participants of said thread to Cc, in case I forgot > something relevant. > > Tomorrow I might have the opportunity to test and reproduce the problem > (I don't know if my train will be an ice4 or one of the older ones > though.) > > I wonder if there is something you want me to test. Without further > input I will try with the modprobe options and check for a minimal > subset of them that makes the problem disappear. > > Is there something I can do to make the problem better understandable > for someone who knows about the hardware? Or to find out the critical > detail about the wifi hotspot that triggers the problem? > > Best regards > Uwe > > [1] https://lists.debian.org/msgid-search/da8c1552-6bcb-14c3-0e86-abcb835ec350@xxxxxxxxx > Hi Uwe, Based on the log, I can understand that it had successfully connected to the AP (supplicant management interface state: associating -> completed); then there're some DHCP errors and eventually the AP sends a deauth. It's hard to say what can cause it, but if you'll be able to reproduce the issue, it'd be great if you could collect a trace-cmd dump with this command: sudo trace-cmd record -e iwlwifi -e mac80211 -e cfg80211 -e iwlwifi_msg It'll be also helpfull if you'll be able to say which specific modprobe option fixes the issue. Thanks, Gregory
