Comment 59 for bug 1222440

See:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1222440/comments/36

"Good config in /etc/modprobe.d/iwlwifi.conf?

caravena@caravena-530U3C-530U4C:~$ cat /etc/modprobe.d/iwlwifi.conf
# /etc/modprobe.d/iwlwifi.conf
# iwlwifi will dyamically load either iwldvm or iwlmvm depending on the
# microcode file installed on the system. When removing iwlwifi, first
# remove the iwl?vm module and then iwlwifi.
remove iwlwifi \
(/sbin/lsmod | grep -o -e ^iwlmvm -e ^iwldvm -e ^iwlwifi | xargs /sbin/rmmod) \
&& /sbin/modprobe -r mac80211
options iwlwifi debug=0xf

 caravena@caravena-530U3C-530U4C:~$ dmesg | grep iw
[ 5.586912] iwlwifi: unknown parameter 'debug' ignored
[ 5.587738] iwlwifi 0000:01:00.0: can't disable ASPM; OS doesn't have ASPM control
[ 5.587825] iwlwifi 0000:01:00.0: irq 43 for MSI/MSI-X
[ 5.599227] iwlwifi 0000:01:00.0: loaded firmware version 18.168.6.1 op_mode iwldvm
[ 5.645474] iwlwifi 0000:01:00.0: CONFIG_IWLWIFI_DEBUG disabled
[ 5.645480] iwlwifi 0000:01:00.0: CONFIG_IWLWIFI_DEBUGFS enabled
[ 5.645484] iwlwifi 0000:01:00.0: CONFIG_IWLWIFI_DEVICE_TRACING enabled
[ 5.645487] iwlwifi 0000:01:00.0: CONFIG_IWLWIFI_P2P disabled
[ 5.645492] iwlwifi 0000:01:00.0: Detected Intel(R) Centrino(R) Advanced-N 6235 AGN, REV=0xB0
[ 5.645567] iwlwifi 0000:01:00.0: L1 Disabled; Enabling L0S
[ 5.668069] ieee80211 phy0: Selected rate control algorithm 'iwl-agn-rs'
[ 10.514169] iwlwifi 0000:01:00.0: RF_KILL bit toggled to disable radio."