First off, I am aware of other people recently posting similar issues but none of the many fixes or suggestions in any thread I've seen has resolved the issue for me.
my ASUS netbook had been working fine for since I got it 6 - 8 months ago but in the past week or so the wifi started randomly freezing/crashing for no discernible reason and none of the normal methods for attempting to fix it yielded any results - only rebooting resolved it.
The first & most obvious method I tried was to restart network-manager, but when I did that I noticed that afterwards wifi showed up as disabled. Further research showed that somehow wifi had gotten hard blocked. There IS a button on the keyboard for wifi and at first I figured I had accidentally hit it but 1) hitting it again does not unblock wifi and 2) ever since I have been hyper-conscious of not hitting it and wifi still randomly gets blocked.
Sometimes I can use the internet for hours and hours with no issue and sometimes after wifi freezes/crashes it will freeze/crash again within minutes of rebooting. It has been at least a week of this happening at least once a day and try as I might I have been unable to figure out any guess as to what is causing or triggering the freezes/crashes.
Fixes I have tried that have not solved the problem:
-restoring BIOS back to defaults
-all manner of rfkill unblocking
-reinstalling wifi drivers
-switching from network-manager to wicd
-unloading & reloading wifi module (brcmsmac)
notably, brcmsmac does not reload once I have sudo modprobe -r 'd it, running sudo modprobe brcmsmac after that yields nothing and at that point running lshw shows the wireless adaptor as "unclaimed." Again, only a reboot fixes this.
other info/details:
The fact that this began within the past week or so seems to me to indicate some kind of update triggered this, but I've been running 14.04 since it was released in April so it would have to have been a more recent, smaller / more minor update that caused this issue if I'm correct in assuming that is what caused it.
lspci -vv
02:00.0 Network controller: Broadcom Corporation BCM4313 802.11bgn Wireless Network Adapter [14e4:4727] (rev 01)
Subsystem: AzureWave Device 2047
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: Memory at f7d00000 (64-bit, non-prefetchable) [size=16K]
Capabilities: <access denied>
Kernel driver in use: bcma-pci-bridge
ifconfig
eth1 Link encap:Ethernet HWaddr 74:d0:2b:71:7d:3f
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Interrupt:19
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:183 errors:0 dropped:0 overruns:0 frame:0
TX packets:183 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:36944 (36.9 KB) TX bytes:36944 (36.9 KB)
wlan1 Link encap:Ethernet HWaddr dc:85:de:56:a4:14
inet addr:192.168.1.111 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::de85:deff:fe56:a414/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:8442 errors:0 dropped:710 overruns:0 frame:0
TX packets:5874 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:5259231 (5.2 MB) TX bytes:1242666 (1.2 MB)
rfkill list (when working)
1: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
2: asus-wlan: Wireless LAN
Soft blocked: no
Hard blocked: no
lshw -C network (when working)
*-network
description: Network controller
product: BCM4313 802.11bgn Wireless Network Adapter
vendor: Broadcom Corporation
physical id: 0
bus info: pci@0000:02:00.0
version: 01
width: 64 bits
clock: 33MHz
capabilities: bus_master cap_list
configuration: driver=bcma-pci-bridge latency=0
resources: irq:17 memory:f7d00000-f7d03fff
*-network
description: Ethernet interface
product: AR8162 Fast Ethernet
vendor: Qualcomm Atheros
physical id: 0
bus info: pci@0000:03:00.0
logical name: eth1
version: 10
serial: 74:d0:2b:71:7d:3f
capacity: 100Mbit/s
width: 64 bits
clock: 33MHz
capabilities: bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=alx latency=0 link=no multicast=yes port=twisted pair
resources: irq:45 memory:f7c00000-f7c3ffff ioport:e000(size=128)
*-network
description: Wireless interface
physical id: 1
logical name: wlan1
serial: dc:85:de:56:a4:14
capabilities: ethernet physical wireless
configuration: broadcast=yes driver=brcmsmac driverversion=3.13.0-32-generic firmware=610.812 ip=192.168.1.111 link=yes multicast=yes wireless=IEEE 802.11bgn
rfkill list (after crashed/frozen):
1: phy0: Wireless LAN
Soft blocked: no
Hard blocked: yes
2: asus-wlan: Wireless LAN
Soft blocked: no
Hard blocked: no
lshw -C network (after crashed/frozen)
*-network
description: Network controller
product: BCM4313 802.11bgn Wireless Network Adapter
vendor: Broadcom Corporation
physical id: 0
bus info: pci@0000:02:00.0
version: 01
width: 64 bits
clock: 33MHz
capabilities: cap_list
configuration: driver=bcma-pci-bridge latency=0
resources: irq:17 memory:f7d00000-f7d03fff
*-network
description: Ethernet interface
product: AR8162 Fast Ethernet
vendor: Qualcomm Atheros
physical id: 0
bus info: pci@0000:03:00.0
logical name: eth1
version: 10
serial: 74:d0:2b:71:7d:3f
capacity: 100Mbit/s
width: 64 bits
clock: 33MHz
capabilities: bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=alx latency=0 link=no multicast=yes port=twisted pair
resources: irq:45 memory:f7c00000-f7c3ffff ioport:e000(size=128)
*-network DISABLED
description: Wireless interface
physical id: 1
logical name: wlan1
serial: dc:85:de:56:a4:14
capabilities: ethernet physical wireless
configuration: broadcast=yes driver=brcmsmac driverversion=3.13.0-32-generic firmware=610.812 link=no multicast=yes wireless=IEEE 802.11bgn
results after running: sudo modprobe -r brcmsmac && sudo modprobe brcmsmac (or any command variation of deactivating & then reactivating or modprobing brcmsmac)
rfkill list
2: asus-wlan: Wireless LAN
Soft blocked: no
Hard blocked: no
basically phy0 dissappears, I'm assuming due to brcmsmac refusing to reactivate
lshw -C network
*-network UNCLAIMED
description: Network controller
product: BCM4313 802.11bgn Wireless Network Adapter
vendor: Broadcom Corporation
physical id: 0
bus info: pci@0000:02:00.0
version: 01
width: 64 bits
clock: 33MHz
capabilities: cap_list
configuration: latency=0
resources: memory:f7d00000-f7d03fff
*-network
description: Ethernet interface
product: AR8162 Fast Ethernet
vendor: Qualcomm Atheros
physical id: 0
bus info: pci@0000:03:00.0
logical name: eth1
version: 10
serial: 74:d0:2b:71:7d:3f
capacity: 100Mbit/s
width: 64 bits
clock: 33MHz
capabilities: bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=alx latency=0 link=no multicast=yes port=twisted pair
resources: irq:45 memory:f7c00000-f7c3ffff ioport:e000(size=128)
basically wireless adaptor shows up as "UNCLAIMED" again I assume related to brcmsmac not reactivating
EDIT
here are a few snippets that appear to be a relevant from /var/log/syslog as requested in comments:
Jul 28 02:20:04 chibitachop wpa_supplicant[1174]: wlan1: CTRL-EVENT-SCAN-STARTED
Jul 28 02:42:32 chibitachop kernel: [29767.677589] brcmsmac bcma0:0: START: tid 1 is not agg'able
Jul 28 02:50:49 chibitachop kernel: [30265.344485] brcmsmac bcma0:0: START: tid 1 is not agg'able
Jul 28 03:05:34 chibitachop kernel: [31149.541093] brcmsmac bcma0:0: START: tid 2 is not agg'able
Jul 28 03:08:35 chibitachop kernel: [31331.008431] brcmsmac bcma0:0: START: tid 2 is not agg'able
Jul 28 17:20:55 chibitachop kernel: [82469.075694] brcmsmac bcma0:0: wl0: brcms_c_watchdog: dead chip
Jul 28 17:20:55 chibitachop kernel: [82469.144339] brcmsmac bcma0:0: ops->tx called while down
Jul 28 17:20:55 chibitachop kernel: [82469.332841] brcmsmac bcma0:0: ops->tx called while down
Jul 28 17:20:56 chibitachop wpa_supplicant[1174]: wlan1: CTRL-EVENT-DISCONNECTED bssid=bc:ee:7b:f3:32:b8 reason=4 locally_generated=1
Jul 28 17:20:56 chibitachop kernel: [82470.179674] brcmsmac bcma0:0: brcmsmac: brcms_ops_bss_info_changed: disassociated
Jul 28 17:20:56 chibitachop kernel: [82470.179688] brcmsmac bcma0:0: brcms_ops_bss_info_changed: arp filtering: 1 addresses (implement)
Jul 28 17:20:56 chibitachop kernel: [82470.179692] brcmsmac bcma0:0: brcms_ops_bss_info_changed: qos enabled: false (implement)
Jul 28 17:20:56 chibitachop kernel: [82470.179697] brcmsmac bcma0:0: wl0: brcms_c_wme_setparams : no-clock
additionally in regards to the other posting this has been marked potentially redundant with, that user has 14e4:432b while mine is 14e4:4727 so the blacklisting procedure is different even if it did work, which as I said in my comment it did not for me.
searching based on error messages found in /var/log/syslog I found this thread from a couple months ago where someone using the same 14e4:4727 Broadcomm as me had similar problems which were never solved: http://ubuntuforums.org/showthread.php?t=2212368&page=4
In response to the post my issue is currently allegedly a duplicate of, which itself redirects to a Broadcomm driver installation guide - that Broadcom installation guide was one of the first posts I found when I began researching this issue. According to that guide my Broadcom card is "Special Case #1 - This device uses the driver combination bcma and brcmsmac. It shouldn't be necessary to install anything at all. Required firmware is installed by default in the package linux-firmware." Despite that, I tried reinstalling the drivers and trying every combination of blacklisting all to no avail as mentioned in my original posting.
As I have said before, my wireless had been working fine for 6 - 8 months since I bought the computer so I know I had the driver configuration right until something somehow messed it up a week or so ago. My only guess as to what could have caused this issue is a change in a recent minor update since I hadn't made any adjustments to any wireless or networking settings since I initially set-up the computer back when I bought it and have been running 14.04 since it was released in April. Nevertheless as I already said one of the first fixes I tried before even posting here was reinstalling / blacklisting drivers as per the very instructions my post is currently marked as a duplicate of and it did NOT resolve the issue.
