On a ThinkPad X230 with this wifi card:
03:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8188CE 802.11b/g/n WiFi Adapter (rev 01)
Subsystem: Realtek Semiconductor Co., Ltd. Device 8195
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Interrupt: pin A routed to IRQ 17
Region 0: I/O ports at 4000 [size=256]
Region 2: Memory at f1c00000 (64-bit, non-prefetchable) [size=16K]
Capabilities: <access denied>
Kernel driver in use: rtl8192ce
...running Ubuntu 14.04, network access is frequently interrupted and sometimes apparently lost for good until a system reboot. At around the time of the interruption, this appears in the system log:
[458.384] cfg80211: Calling CRDA to update world regulatory domain
[458.384] wlan0: authenticate with 00:13:10:ee:af:97
[458.385] wlan0: send auth to 00:13:10:ee:af:97 (try 1/3)
[458.389] cfg80211: World regulatory domain updated:
[458.389] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[458.389] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[458.389] cfg80211: (2457000 KHz - 2482000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[458.389] cfg80211: (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
[458.389] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[458.389] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[458.390] wlan0: authenticated
[458.390] rtl8192ce 0000:03:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP
[458.390] rtl8192ce 0000:03:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP
[458.391] wlan0: associate with 00:13:10:ee:af:97 (try 1/3)
[458.393] wlan0: RX AssocResp from 00:13:10:ee:af:97 (capab=0x401 status=0 aid=3)
[458.394] wlan0: associated
[984.594] wlan0: deauthenticated from 00:13:10:ee:af:97 (Reason: 7)
The access point is a WRT54GS running Tomato 1.19. I have several other wireless devices around - another laptop, an iPad, an Android phone. There are no other wireless devices in range (no neighbors, no other access points, etc).
The laptop is new (to me), from the first time I opened the lid this was the behavior (in other words it didn't start out working properly and then get broken by a system update or something).
I've read that "Reason: 7" is "Class 3 frame received from nonassociated STA". I guess "STA" is short for "station" which maybe is the same kind of thing as an access point. It doesn't seem like this should happen since there are no other access points in range (it is miles to the next access point).
What's up? Can I fix this somehow or is this hardware simply not well supported on Ubuntu 14.04?