Ubuntu Wiki

General Info

Escalating bugs and issues to the upstream developers is important to improving the overall quality of wireless drivers. Before we get started we will review first a few general details about the life cycle of Ubuntu's kernel releases so you are more comfortable with how things get into Ubuntu and what you are using.

Bug Report Minimum Requirement Information

• When providing information for a bug to be worked on by a developer, please mention the following information:
  • If you update your BIOS to the newest version, does this change anything?
  • What is the wireless access point manufacturer, model, firmware version and settings:
    • Encryption Type (ex. WEP, WPA2-PSK TKIP/AES)
    • MAC Filtering
    • QoS/WMM
    • Beacon Interval
    • Router Internal Firewall
      • If you change any of these settings does it change anything?

  • What WiFi connection type are you using (e.g. 802.11n, 802.11g, etc.)? If you change the connection type, does it change anything?

  • Does another WiFi device tested with the AP have the same problem as the hardware you initially reported with?

  • What is the distance of the WiFi device from AP? What is the number and type of obstructions between the two? If you bring the device close to the AP and eliminate obstructions, does this change anything?

  • Does the issue occur with different APs?

  • Is it a regression (e.g. did the problem happen in a prior Ubuntu release)? If you do not know, could you please test for this in the earliest release of Ubuntu that is supported as per Ubuntu Releases?

  • Does compat-wireless provide a WORKAROUND or solution following https://wiki.ubuntu.com/Kernel/LinuxWireless#Compat-wireless_in_Ubuntu ?

  • Does this problem occur in the newest mainline kernel following https://wiki.ubuntu.com/Kernel/MainlineBuilds ?

  • Does ndiswrapper provide a WORKAROUND or solution following https://help.ubuntu.com/community/WifiDocs/Driver/Ndiswrapper ?

  • For Broadcom WiFi chipsets, does the proprietary Broadcom STA wireless driver provide a WORKAROUND or solution following https://help.ubuntu.com/community/BroadcomSTA%28Wireless%29 ?

  • For Realtek WiFi chipsets, does the Realtek Backport PPA provide a WORKAROUND or solution following https://launchpad.net/~lexical/+archive/hwe-wireless ?

Ubuntu's kernels

During the Ubuntu development cycle, which happens every 6 months, the Ubuntu kernel will pick the latest stable kernel release available. At Ubuntu's Intrepid release cycle, for example, this was the 2.6.27 kernel, for Jaunty this was the 2.6.28 kernel, and for Karmic 2.6.31.

The Linux wireless guide on reporting bugs

Please be sure to read this guide, then finish this guide.

http://wireless.kernel.org/en/users/Documentation/Reporting_bugs

The Ubuntu proposed repository

Keep in mind Ubuntu has a "proposed" repository which allows you get newer kernels stable kernels (if you are 2.6.27.10 the proposed repository may have a 2.6.27.14 kernel). For Intrepid this would look like in /etc/apt/sources.list:

deb http://us.archive.ubuntu.com/ubuntu/ intrepid-proposed main restricted
deb-src http://us.archive.ubuntu.com/ubuntu/ intrepid-proposed main restricted

On Jaunty:

deb http://us.archive.ubuntu.com/ubuntu/ jaunty-proposed main restricted
deb-src http://us.archive.ubuntu.com/ubuntu/ jaunty-proposed main restricted

On Karmic:

deb http://us.archive.ubuntu.com/ubuntu/ karmic-proposed main restricted
deb-src http://us.archive.ubuntu.com/ubuntu/ karmic-proposed main restricted

The kernels are propagated over time from the proposed repository to updates over a few weeks period of time after general testing and acceptance.

Ubuntu Intrepid kernel release to stable kernel map

Unfortunately Ubuntu's Intrepid kernels do not tell you what the extraversion (the .10 in 2.6.27.10) and this is required to report bugs upstream. Because of this you can look at the Ubuntu kernel version --> detailed mainline kernel version map to find out what exact upstream mainline kernel your kernel is based on.

For example if you get:

ogasawara@emiko:~$ cat /proc/version_signature
Ubuntu 2.6.27-10.20-generic

You can then look at the map as to what exactly this maps to. In this case this would map to the 2.6.27.7 kernel.

It should be noted that the /proc/version_signature is an Ubuntu specific feature to help you get the detailed kernel version.

Compat-wireless in Ubuntu

Ubuntu packages compat-wireless in the linux-backports-modules package.

For Precise, this may be done by executing the following at a terminal:

sudo apt-get -y install linux-backports-modules-cw-3.3-3.2.0.23-generic-pae
sudo reboot

For Intrepid Ibex 8.10, linux-backports-modules can be installed by running the following command from a Terminal:

sudo apt-get install linux-backports-modules-intrepid
sudo reboot

You will probably get newer version of this package if you enable the proposed repository are explained above in this section.

It should be noted that linux-backports-modules is updated regularly but not every day. If you want to ensure you are running bleeding edge you are better off using compat-wireless directly. Also keep in mind that linux-backports-modules installs modules in /lib/modules/$(uname -r)/updates/ and upon removal the modules are not removed. So be sure to rm -rf that updates directory (and only the updates directory!).