Tuesday, 25 April 2017

RTL8723BS wifi soon to hit mainline kernel


Bastien Nocera's RTL8723BS wifi github (hadess/rtl8723bs) has been merged into the kernel staging tree and as a result the compiling of the driver as an external module or running the driver on older kernels is no longer supported and the repository now only contains the history of the driver cleanup which is not available in the upstream-merged driver. As the final commit states:
The driver is available upstream now in the linux-next tree, in
the staging drivers section. All tests, bug reports should be
made to the linux-wireless mailing-list, using this upstream driver.
Consider the existence of this GitHub repository as historical
documentation. Patches that were shipped as part of this repository have
mostly been subsided and obsoleted by upstream kernel fixes.
Support for Bluetooth, and the firmware files are also in the process
of being made available upstream, and will be removed when that happens.
If all goes to plan it should appear in mainline kernel 4.12-rc1 whose merge window should open next week barring any last minute issues with the first builds appearing in early May.

I've consequently retired my script 'linuxium-install-rtl8723bs.sh' as we look forward to the upcoming mainline support.

Saturday, 22 April 2017

Creating personalized Ubuntu, Mint and Debian ISOs for Intel Mini PCs



Normally Linux distribution ISOs work perfectly when written to a USB for booting as a 'Live USB' allowing both usage and installation of the distro. Unfortunately with the introduction of Intel Atom based mini PCs the issue of requiring a 32-bit bootloader to boot a 64-bit OS arose. Further complications were caused by the lack of mainline support for HDMI audio and wifi resulting in the use of custom kernels. And now even with mainline support soon to eventuate there is still a lead time required by distributions before they incorporate the latest kernels.


To solve the issue of using a standard ISO but with a different kernel I developed a script that allows the ISO to be respun with the latest kernel build. But because new kernel builds are released weekly I extended the script to allow the respinning with a specified kernel.


However I always end up installing the same set of packages immediately after installation so I thought it would be useful if packages could be included during the respin. Equally adding locally compiled packages became another requirement as it allowed the respinning of ISOs to include custom kernels or third party applications like Google Chrome. 


Another limitation was that after installation I found myself wanting to run scripts to fix or add functionality like audio and wifi. So being able to incorporate these as part of a personalized ISO would simplify both the installation process and provide a more functional Live USB.


​The last issue I encountered was trying to boot an ISO on a new Apollo Lake mini PC. As the GRUB bootloader failed to boot Ubuntu I switched to using the rEFInd boot manager to allow Linux to boot itself. In doing so I solved another want I've sometimes wished for when using a Live USB namely the lack of persistence or the ability to save files such as screenshots or error messages that could still be accessed after rebooting. So I rewrote my script to include all these features. 

The invocation although command line based is really quite simple:

Usage: ./isorespin.sh [-h|-v] | [[-u | -k <kernel>] | -p "package_1 ... package_n" | -l "package_1.deb ... package_n.deb" | -a "file_1 ... file_n" | -r [-s <size><MB|GB>]] -i <ISO>

Functionality is achieved by calling the command with flags and arguments or options with parameters and these are as follows:
-u or --update will update an Ubuntu based ISO (e.g. Ubuntu or one of its flavours or Linux Mint) to the latest Ubuntu Kernel Team released mainline build. For a Debian based ISO (e.g. Debian Live or LMDE) using this option will update the current v3.16 kernel with the Canonical DKMS patches for HDMI audio and RTL8723BS wifi.
-k or --kernel replaces an Ubuntu based ISO's kernel with the one specified by the argument or parameter which can be any of the Ubuntu Kernel Team kernel builds located at http://kernel.ubuntu.com/~kernel-ppa/mainline (just use the directory or folder name without the trailing '/' as in '--kernel v4.11-rc7' noting that earlier kernels will probably not work well if at all).
-p or --package will install a single package or a set of packages (if enclosed in quotes) that are available to the ISO (which can be either Ubuntu or Debian based) and would typically would be installed using 'apt install <package>' command.
-l or --local allows local Debian binary packages to be installed within the respun ISO. Care must be taken in specifying the order of multiple packages to preserve any dependencies and of course all dependencies must be met for the packages to be successfully installed.
-a or --add allows local binaries or shell scripts to be saved under '/usr/local/bin' on the respun ISO although there is no limitation on the actual type of file itself so any file can be added if required.
-r or --refind will add the rEFInd boot manager which can be selected using the device's boot manager at boot time.
-s or --storage adds persistence to the respun ISO. Although a size must be specified there is some flexibility on how much is allocated. The minimum size is 100MB which keeps the size of the ISO down but means that once the USB is created the persistence partition should be manually resized for typical usage. Alternatively a larger size can be specified thus avoiding the immediate need to resize as this can always be performed later. It is recommended to use a realistic amount somewhere between 1GB and 2GB to maintain the balance between a practical but usable ISO. 
-i or --iso must be specified and is the location of the ISO to be respun.
Depending on the options and their complexity the respin will take a few minutes and the script provides updates its progress whilst running. The respun ISO is created with a new name derived from the original ISO name and includes indicators of the options used like 'persistence' or the kernel name or 'dkms' for example. It is recommended that around 10GB of space is available for the script to function correctly and an internet connection is typically required for some options like kernel updates for example. The script runs on Debian/Ubuntu based distros and requires certain packages to be installed prior to running although it checks and notifies if anything is missing first before continuing. Also the rEFInd bootmanager (http://www.rodsbooks.com/refind) can be downloaded from https://sourceforge.net/projects/refind/files into the same directory as the script to prevent unnecessary repeated downloads if this is a concern and will make processing quicker.

Once the ISO has been respun it can be written to a USB using the standard 'dd' command. 

To perform a manual resize when using a USB with persistence first use the device's boot menu to select the USB and when the rEFInd screen appears click on 'F2' twice. A text line will appear at the top of the screen so use the arrow keys to move the cursor and delete the word 'persistence' or 'persistent' depending on whether it is an Ubuntu or Debian based ISO. This step actually disables persistence and is only required so that the partition is not auto mounted thus preventing resizing. Now press the enter key to boot. 

\

Once booted use the 'gparted' command to resize the persistence partition. You will be prompted to fix the GPT to use all the available space so click 'Fix' and then continue with the resizing. 



An example invocation is as follows:

./isorespin.sh -i ubuntu-17.04-desktop-amd64.iso -k v4.11-rc5 -a "../scripts/wifi/linuxium-install-rtl8723bs-binaries-for-4.11.0-rc5.sh ../scripts/linuxium-install-UCM-files.sh" -p "ssh openssh-server inxi" -l google-chrome-stable_current_amd64.deb -r -s 2GB

This will respin the latest Ubuntu 'Zesty' ISO and make the boot kernel the fifth release candidate of the latest development mainline kernel. It will add my script for installing wifi for the RTL8723BS chip on this specific kernel version under '/usr/local/bin' along with adding another script to install the UCM files required for headphone audio on certain Intel Atom mini PCs. It will also install the 'ssh', 'openssh-server' and 'inxi' packages along with 'Chrome' so they are all available for immediate use on a 'Live USB' and will be included as part of a standard installation. It will also include a persistence partition of 2GB and the resultant ISO produced as: 

linuxium@LINUXIUMONE:~$ ls -l linuxium-persistence-rEFInd-v4.11-rc5-ubuntu-17.04-desktop-amd64.iso
-rw-r--r-- 1 linuxium linuxium 4215292928 Apr 22 12:43 linuxium-persistence-rEFInd-v4.11-rc5-ubuntu-17.04-desktop-amd64.iso
linuxium@LINUXIUMONE:~$ 

The script currently supports all recognized Ubuntu and Ubuntu flavoured ISOs (https://www.ubuntu.com/download/ubuntu-flavours), Linux Mint and LDME ISOs (https://www.linuxmint.com/download.php), Debian 'Live install' ISOs (https://www.debian.org/CD/live), KDE neon ISOs (https://neon.kde.org/download), elementary OS ISOs (https://elementary.io) and Kali ISOs (https://www.kali.org/downloads). Any issues or improvement suggestions are welcome. It can be downloaded from isorespin.sh.

Please donate if you find the script useful using the following link http://goo.gl/nXWSGf as everything helps with development costs.

Thursday, 13 April 2017

Improved 'isorespin' with choice of kernels and Debian 'Live' ISO support

Although Debian have released 'Live' ISOs for some time, I've always had problems getting them to boot on Intel Atom Bay Trail and Cherry Trail devices. But with the news of Canonical dropping Unity in favour of Gnome and with the rise in popularity of Linux Mint and their Cinnamon and Mate editions, I thought I'd revisit Debian and see whether my 'isorespin' script could be adapted to make a difference.


After modifying my script to successfully boot a Debian 'Live' ISO (see https://www.debian.org/CD/live for details and http://cdimage.debian.org/debian-cd/current-live/amd64/iso-hybrid for downloadable images) I realised that as the kernel was version 3.16 the original Canonical Intel Atom DKMS packages could be applied to provide HDMI audio and RTL8723BS wifi.


Unfortunately it does mean that the same old problems are back in that HDMI audio only works with a device booting from a 64-bit bootloader (otherwise it is back to DSDT patching for 32-bit devices) and audio is flakey to the point of not being really usable on desktops like LXDE.


However it does mean that LMDE (Linux Mint Debian Edition) gains the critical functionality making it more useable.


At the same time I thought it would be interesting to be able to have a choice in what kernel an Ubuntu based ISO could be respun with. Not only does the Ubuntu Kernel Team release mainline builds but they also provide builds based on the 'drm' sub-tree and have recently (albeit again) included kernels built on 'drm-intel-nightly'. These are particularly useful is seeing what new functionality is further upstream than the mainline release candidate builds.


As well any Ubuntu mainline kernel build can be installed up to the latest release candidate.


I've included all this functionality into a new release of my 'isorespin' script. And as such I've had to change the invocation or syntax for running the script slightly.

Usage: ./isorespin.sh [-h|-v] | [-u | -k <kernel>] -i <ISO>

The script can be downloaded from isorespin.sh and when executed as a command has new parameters that support both short and long form when defining options. Besides a '-h' or '--help' that shows the syntax and a '-v' or '--version' to display the version, the ISO that you want respun must now be specified by the '-i' or '--iso' flag. The ISO can either be an Ubuntu, Ubuntu flavour, Linux Mint or Debian ISO and can be modified by further options. The '-u' or '--update' flag will update an Ubuntu or Linux Mint ISO with the latest mainline kernel. But when used with a Debian or LMDE ISO it will update the kernel with the Canonical DKMS patches for HDMI audio and RTL8723BS wifi. The '-k' or '--kernel' option is only allowed for Ubuntu and Linux Mint ISOs and any of the Ubuntu Kernel Team kernel builds found at http://kernel.ubuntu.com/~kernel-ppa/mainline can be specified by using the directory/folder name without the trailing '/' (as in '--kernel v4.11-rc6'). Note that the earlier kernels will probably not work well if at all.

For anyone brave enough to try an installation of the non-Ubuntu ISOs you may encounter the usual issues with installing a bootloader. To help I've written an additonal script 'linuxium-install-bootloader.sh' that even if it doesn't work directly, the commands within the script should provide a good enough guide to allow you to install manually. Note that running the script requires an internet connection and the target Linux partition needs to be already mounted on '/target' with the target boot partition mounted on '/target/boot/efi'.

If you like the scripts then please donate using the following link http://goo.gl/nXWSGf as everything helps with development costs.

Wednesday, 5 April 2017

isorespin.sh Now With Mint and Cinnamon


Besides Ubuntu and flavours you can now respin Linux Mint ISOs and if required update them with the latest Canonical build of an upstream kernel and boot them on Cherry Trail and Bay Trail devices with either a 32-bit bootloader or a 64-bit bootloader.

To respin an existing Linux Mint ISO you will need to use a Linux machine with 'squashfs-tools' and 'xorriso' installed (e.g. 'sudo apt install -y squashfs-tools xorriso') and a working internet connection with at least 10GB of free space. Having downloaded an ISO (for example 'linuxmint-18.1-cinnamon-64bit.iso' simply download my script isorespin.sh and run with the ISO as a parameter (e.g. './isorespin.sh linuxmint-18.1-cinnamon-64bit.iso'). Or to respin and update the kernel include a '-u' or '--update' option (e.g. './isorespin.sh --update linuxmint-18.1-cinnamon-64bit.iso').

For wifi with the RTL8723BS chipset you can either download and run linuxium-install-rtl8723bs.sh which will build the wifi and bluetooth drivers from source but requires a working internet connection or you can download and run linuxium-install-rtl8723bs-binaries-for-4.11.0-rc5.sh which installs prebuilt binaries from the same source but does not require the internet. This second script only works for the Canonical built upstream kernel defined by the script name.

For wifi using Broadcom chipsets you can download and run linuxium-install-broadcom-drivers.sh which should get wifi and bluetooth working for most of the popular Broadcom chipsets.

The bluetooth service requires 'systemd' to be installed which should be by default on recent ISOs otherwise a manual configuration is required to run the service.

If you have a headphone jack you can update the UCM files once you have an internet connection by downloading and running linuxium-install-UCM-files.sh which provides audio for devices with the 5640 and 5640 chipsets.

For more detailed information see my post Running Ubuntu with an Upstream Kernel on Intel Bay and Cherry Trail Devices and don't forget to donate using the following link http://goo.gl/nXWSGf as everything helps with development costs.

Wednesday, 29 March 2017

Running Ubuntu with an Upstream Kernel on Intel Bay and Cherry Trail Devices



In the past Intel Atom based mini PCs with Bay Trail and Cherry Trail SOCs required customized kernels to provide HDMI audio. As of version 4.11 the mainline kernel will include support for HDMI audio on Intel Atom SoCs and early release candidates are already available. The latest mainline kernel also includes a number of other patches including AXP288, I2C and the latest anti-freeze patches. Canonical build upstream kernels based on these release candidates and they have just released 'deb' packages using the first Ubuntu version 4.11 kernel configuration file.

In anticipation that the v4.11 kernel will be included in Ubuntu 17.10 thereby removing the basic need for customized kernels, I am now providing an interim migration path that allows the latest v4.11 Ubuntu kernel build to be used with Ubuntu ISOs.



Using a script that I've developed you can respin an existing Ubuntu ISO so that you can boot it from a device with either a 32-bit bootloader or a 64-bit bootloader and optionally update it with the latest Canonical Ubuntu build of an upstream kernel.

Update: 
Linux Mint ISOs are now supported using the updated version of the script isorespin.sh

To respin an existing Ubuntu ISO you will need to use a Linux machine with 'squashfs-tools' and 'xorriso' installed (e.g. 'sudo apt install -y squashfs-tools xorriso') and a working internet connection with at least 10GB of free space. Having downloaded an ISO (for example 'ubuntu-16.04.2-desktop-amd64.iso' simply download my script isorespin.sh (see Update: below for the latest version) and run with the ISO as a parameter (e.g. './isorespin.sh ubuntu-16.04.2-desktop-amd64.iso'). Or to respin and update the kernel include a '-u' or '--update' option (e.g. './isorespin.sh --update ubuntu-16.04.2-desktop-amd64.iso'). Note: if you get the unexpected error 'File must be an Ubuntu ISO ... exiting.' when running the script on a non-Ubuntu platform then make the following one-off update to the script by running the command 'sed -i "49,53d;59d" isorespin.sh' which should then enable it to run without issue.

You can respin the latest available ISOs include the recently released 17.04 Beta 2 of any flavour including Ubuntu, Lubuntu, Xubuntu etc, as well as respinning earlier releases such as 16.04.2 or 14.04.5 for example.



As some wifi/bluetooth driver and userspace files are still required I've provided additional scripts to support RTL8723BS and various Broadcom chipsets as well as the ALSA UCM files for some audio chipsets used for headphones. The scripts can be run whilst using the ISO as a 'LiveCD' to provide wifi connectivity (assuming they have been previously downloaded and are accessed from USB or similar). Once an ISO has been installed the scripts can be run to install the additional functionality.

For the RTL8723BS chipset your first option is to download and run linuxium-install-rtl8723bs.sh which will build the wifi and bluetooth drivers from source and this requires a working internet connection. Alternatively you can download and run linuxium-install-rtl8723bs-binaries-for-4.11.0-rc4.sh (see Update: below for the latest version) which installs prebuilt binaries from the same source but does not require the internet. This second script only works for the Ubuntu built upstream kernel defined by the script name.

For Broadcom chipsets you can download and run linuxium-install-broadcom-drivers.sh which should get wifi and bluetooth working for most of the popular Broadcom chipsets (as I don't have the devices to do extensive testing unfortunately). If you run this script with an internet connection it will also update the Broadcom firmware with the latest upstream firmware from Google's ChromiumOS which may help for other Broadcom based devices.

Note that in both cases the bluetooth service requires 'systemd' (as used by 17.04 and 16.04) so earlier Ubuntu versions will need a manual configuration to run the service.

Finally for updating the UCM files where you have a headphone jack you will need an internet connection before downloading and running linuxium-install-UCM-files.sh which provides audio for devices with the 5640 and 5640 chipsets.

A new kernel release candidate is released each week prior to the final version and you can go to http://kernel.ubuntu.com/~kernel-ppa/mainline/?C=N;O=D to check the latest version which will be displayed first.

If you want to respin ISOs with a release candidate later than 'rc4' simply edit 'isorespin.sh' and change the first couple of lines
MAINLINE_BRANCH="v4.11-rc4"
MAINLINE_KERNEL_VERSION="4.11.0-rc4"
to match the required version.

Update:
Mainline kernel v4.11-rc5 includes a new patch for the RTL8723BS wifi driver that improves speed and reliability. So I've uploaded an updated version of my script isorespin.sh preconfigured for v4.11-rc5 together with a new script linuxium-install-rtl8723bs-binaries-for-4.11.0-rc5.sh which installs the prebuilt wifi and bluetooth binaries compiled for v4.11-rc5. This version of the script now additionally supports Linux Mint ISOs.

Finally if you find my work useful then please donate using the following link http://goo.gl/nXWSGf as everything helps with development costs.

Monday, 6 March 2017

Comparing Ubuntu Flavours Popularity

Ever since I've provided Ubuntu ISOs I've always been interested in knowing what gets downloaded the most verses the least in order to focus my work on where the interest is. Unfortunately because Google Drive doesn't offer file specific download statistics as a workaround I started using Google URL Shortener for each ISO's download link as it provides a counter.

Using the counter for each ISO I created the following table showing each Ubuntu flavour as a percentage of the total downloads for recent releases:


Initially I thought the results might be slightly skewed as Ubuntu has always been provided first before the other flavours. However as the total number of downloads is large for both releases I don't think this has caused any statistical anomaly.

I'm currently using these counter statistics to decide the priority for uploading new releases. So if you were wondering what happened to the 16.04.2 Kubuntu ISO now you know.

Wednesday, 1 March 2017

Ubuntu 16.04.2 and Ubuntu 17.04 Beta 1 plus flavours

Please note my blog is intended to be the 'dynamic' update content partner to my 'static' core content pages on my website. This particular post relates to my http://www.linuxium.com.au/how-tos/runningubuntuontheintelcomputestick page where I've created some Ubuntu ISOs whose purpose is to better support Intel Atom based devices. 

As Canonical just released Ubuntu 16.04.2 with the rolling Hardware Enablement (HWE) kernels which aim to provide support for the latest hardware I've decided to provide a single kernel which is effectively a HWE 'edge' kernel specifically patched for Intel Atom SoCs in my ISOs to simplify kernel management and create a forward path for future migration to mainline kernels.

My kernel is based on Canonical's next 'zesty' kernel which is rebased to v4.10 and also available in 'xenial' as hwe-edge. Whilst v4.10 is the latest mainline kernel to be released the merge window for v4.11 now includes the revised HDMI LPE Audio Support patch set together with the AXP288 power supply patch set for Intel Atom SoCs. Because v4.11 will be released in a couple of months with the patches being included in Ubuntu hopefully by 17.10 I've added these latest patches from the merge window to my kernel. Besides the HDMI LPE patches from Pierre-Louis Bossart, Jerome Anand & Takashi Iwai and Hans de Goede's AXP288 patches I've also added Hans de Goede's PWM, I2C, CX2702X audio support, Silead touchscreen support and ASUS tablet function key support patches. Also included is Mika Kuoppalad's new anti-freeze patch, Pierre-Louis Bossart's PMC Platform Clock and Codecs patches, Ville Syrjälä atomic update fix, Bastien Nocera's wifi patch, Laszlo-Fiat's bluetooth patch, Jonas Aaberg's bluetooth patch for the ASUS 100HA together with my bluetooth support which is based on a script from Larry Finger. The kernel source is available on my github.

At this stage I'm providing ten ISOs: 16.04.2 releases of Ubuntu, Lubuntu, Xubuntu, Ubuntu MATE, Ubuntu GNOME and Kubuntu all with kernel Ubuntu-lts-4.10.0-10.12~16.04.2 together with Ubuntu 17.04 pseudo Beta 1 and 17.04 Beta 1 releases of Lubuntu, Xubuntu and Ubuntu Budgie all with kernel Ubuntu-4.10.0-10.12. Technically the two kernels are the same with the 'xenial' LTS kernel being a backport of the 'zesty' kernel. Note that the Ubuntu 17.04 Beta 1 is a pseudo release because there is no official Beta 1 release so I have used the daily release provided the same day the official Beta 1 flavours were released. I've also included Ubuntu Budgie as it is now an official Ubuntu flavour and I thought there may be some interest. Further flavours will be added later although I am no longer going to provided updated 16.10 releases due to resource constraints. I am also providing the corresponding kernel update scripts and I will maintain the kernels with security patches and/or Intel Atom SoC added functionality/improvements.

To try an ISO download it from the link below (in red) and write it to a USB using either 'Rufus' in Windows or 'dd' in Linux.

16.04.2

Ubuntu 16.04.2
(sha256sum 72832bfc886b2e0beede4f33e7703b4c2c47ef0baae1a3064fb6ab70892ee689)
Ubuntu comes with everything. All the essential applications, like an office suite, browsers, email and media apps come pre-installed and thousands more games and applications are available in the Ubuntu Software Centre.
.
(sha256sum e1102f37c35d1e77f515cc0574388eec700831288ecc7e8fe73ca8755eb5a5ef)
Lubuntu is a fast, energy saving and lightweight variant of Ubuntu using LXDE. It is popular with PC and laptop users running on low-spec hardware.

(sha256sum c33862d036885b41e1cc0c438b0008a14fc3495b352f8f2240fbe3843ac1fc31)
Xubuntu is an elegant and easy to use operating system. Xubuntu comes with Xfce, which is a stable, light and configurable desktop environment.

Ubuntu MATE 16.04.2
(sha256sum d2d4e07cc2121a90617b94904800e60498792bf7f5736157cc7a833efe211947)
Ubuntu MATE expresses the simplicity of a classic desktop environment. MATE is the continuation of the GNOME 2 desktop which was Ubuntu's default desktop.


Ubuntu GNOME 16.04.2
(sha256sum 0b4e7d175b79e89b35e0449af07f4b96bed28e5912d5f43a11bbc54e122460ed)
Ubuntu GNOME uses GNOME Shell along with a plethora of applications from the GNOME Desktop Environment.


Kubuntu 16.04.2
(sha256sum 3d6f1ee5db819bb0e44167efae818b9ae86a9335eca1e187291b3b31a1797ff0)
Kubuntu offers the KDE Plasma Workspace experience, a good-looking system for home and office use.



17.04 Beta 1

(sha256sum f38dcc8fc64f524422028b24e8e95ebe7635241aa24edbdafeeb55dd44c5d36c)
Ubuntu comes with everything. All the essential applications, like an office suite, browsers, email and media apps come pre-installed and thousands more games and applications are available in the Ubuntu Software Centre.

Lubuntu 17.04 Beta 1
(sha256sum f8a8af2d453a58a8538f9f76ceac29a1e2477793c59d373f0bddda5c3338d35f)
Lubuntu is a fast, energy saving and lightweight variant of Ubuntu using LXDE. It is popular with PC and laptop users running on low-spec hardware.
(sha256sum 2a1770e0e51921328224d5c477027420fee3f9bfc715ddb741adf75409f20afb)
Xubuntu is an elegant and easy to use operating system. Xubuntu comes with Xfce, which is a stable, light and configurable desktop environment.
(sha256sum bc92e6df5b4c298fc877743ab0303d7272ec87bc7a40e79ddf80f0883dc6c8ea)
Ubuntu Budgie is stable and easy to use that integrates the Budgie Desktop environment into Ubuntu. Whether you are using it on the old computer, or powerful workstation, Ubuntu Budgie is adaptable to any device, keeping them fast and usable.

If freezing persists follow Len Brown suggestion of adding "intel_idle.max_cstate=2" as a kernel boot parameter which enables Core-C6 but disables module/package-C6. Open a terminal session and enter the following command (on a single line) 'sudo sed -i 's/\(GRUB_CMDLINE_LINUX=\)""/\1"intel_idle.max_cstate=2"/' /etc/default/grub'. To implement the change enter 'sudo update-gruband then reboot the system by entering 'sudo reboot'. The above change only needs to be made once, typically following installation to eMMC storage. Prior to embarking on an encrypted LVM installation you should first open a terminal session and turn off swapping using the command 'sudo swapoff -a'. If there is no wifi after booting devices with a Broadcom chip then reload the driver: in a terminal window enter 'sudo modprobe -r brcmfmac' followed by 'sudo modprobe brcmfmac'. Occasionally on some devices bluetooth doesn't initially load so it is necessary to restart the service: for Broadcom chip devices enter 'sudo systemctl stop brcmbt.service' followed by 'sudo systemctl start brcmbt.service' and for Realtek chip devices enter 'sudo systemctl stop rtl8723bsbt.service' followed by 'sudo systemctl start rtl8723bsbt.service'. Some devices still do not reboot (or warm restart) correctly which can result in a purple screen or lack of wifi and/or bluetooth on reboot. In these circumstances cycle the power and boot the device from cold. Unfortunately as I don't have a tablet I cannot advise on the screen rotation issues however others have commented in previous posts with their solutions which I'd recommend reading. WIP includes improving backlight support for some devices and the ES8316 driver which is currently under development.


Kernel update scripts are provided for updating the kernel and require my ISOs to be installed as a pre-requisite otherwise you will be missing the 'userland' files required for audio, wifi and bluetooth. To upgrade the existing installed kernel to the later version provided by the script first download the script and after making it executable (enter 'chmod 755 ~/Downloads/<script>') install it as 'root' (by entering 'sudo ~/Downloads/<script>'). Once the script has finished executing the device will need to be rebooted to use the updated (patched) kernel. 

4.10.0-10.12 (latest zesty kernel)
4.10.0-10.12~16.04.2 (latest backported xenial kernel)

Don't forget when making a comment to include the name/model of your device and if reporting a technical issue please include a copy of the output from 'dmesg' by sharing the log using 'pastebinit' or similar.