ChromeOS version: 61.0.3163.124 (9765.81.0)
Device model: Guado (ASUS Chromebox CN62)
Case#: 14331643

Description:

Enterprise customer reported their Cfm devices keep dropping out of video meetings, about 10 min after joining. It seems Cfm crashes at around the date/time of issue, and all crash reports seem to be triggered by kernel warning.

Sample crash report: crash/d17c9cb3753792f2

From ChromeOS debug log, kernel warning suggests device received invalid WMM params from AP:

2017-11-30T11:07:53.815785-05:00 INFO kernel: [   94.193350] wlan0: AP has invalid WMM params (AIFSN=0 for ACI 0), will use 2
2017-11-30T11:07:53.815787-05:00 INFO kernel: [   94.193355] wlan0: AP has invalid WMM params (AIFSN=0 for ACI 1), will use 2
2017-11-30T11:07:53.815788-05:00 INFO kernel: [   94.193360] wlan0: AP has invalid WMM params (AIFSN=0 for ACI 2), will use 2
2017-11-30T11:07:53.815795-05:00 INFO kernel: [   94.193365] wlan0: AP has invalid WMM params (AIFSN=0 for ACI 3), will use 2
2017-11-30T11:07:53.815796-05:00 WARNING kernel: [   94.193369] ------------[ cut here ]------------
2017-11-30T11:07:53.815797-05:00 WARNING kernel: [   94.193380] WARNING: CPU: 1 PID: 6 at /mnt/host/source/src/third_party/kernel/v3.14/drivers/net/wireless-3.8/iwl7000/mac80211/driver-ops.c:175 drv_conf_tx+0x7f/0x119 [iwl7000_mac80211]()
2017-11-30T11:07:53.815798-05:00 NOTICE kernel: [   94.193389] wlan0: invalid CW_min/CW_max: 0/0
...
2017-11-30T11:07:53.815830-05:00 WARNING kernel: [   94.193671] ---[ end trace 76dc4abdfc008d5f ]---
2017-11-30T11:07:53.815830-05:00 ERR kernel: [   94.193676] wlan0: failed to set TX queue parameters for AC 0
2017-11-30T11:07:53.815831-05:00 ERR kernel: [   94.193681] wlan0: failed to set TX queue parameters for AC 1
2017-11-30T11:07:53.815832-05:00 ERR kernel: [   94.193685] wlan0: failed to set TX queue parameters for AC 2
2017-11-30T11:07:53.815833-05:00 ERR kernel: [   94.193690] wlan0: failed to set TX queue parameters for AC 3
2017-11-30T11:07:53.826618-05:00 INFO kernel: [   94.203625] wlan0: associated
2017-11-30T11:07:53.829545-05:00 INFO crash_reporter[2637]: Processing kernel warning: normal collection
2017-11-30T11:07:53.830710-05:00 INFO crash_reporter[2637]: Stored kernel warning into /var/spool/crash/kernel_warning.20171130.110753.0.kcrash
...
2017-11-30T11:17:20.497627-05:00 NOTICE crash_sender[3793]: Sending crash:
2017-11-30T11:17:20.498106-05:00 NOTICE crash_sender[3794]:   Metadata: /var/spool/crash/kernel_warning.20171130.110753.0.meta (kcrash)
2017-11-30T11:17:20.498519-05:00 NOTICE crash_sender[3795]:   Payload: /var/spool/crash/kernel_warning.20171130.110753.0.kcrash
2017-11-30T11:17:20.499417-05:00 NOTICE crash_sender[3797]:   Exec name: kernel-warning
2017-11-30T11:17:21.803189-05:00 NOTICE crash_sender[3809]: Crash report receipt ID d17c9cb3753792f2

Log: https://drive.google.com/file/d/1Kh-Gewazv-JdDmgD2fhWMm0yGx9fA448/view?usp=sharing
Customer info: https://docs.google.com/document/d/1WOm4HQFB8pDyvVa1a_RUKgXuEbuSxVXrmgd605JflkQ/edit?usp=sharing