DVB issue since LE switched to kernel 4.9.x

    OK - I've compiled the most recent version of 4.8.y from GitHub - raspberrypi/linux: Kernel source tree for Raspberry Pi Foundation-provided kernel builds. Issues unrelated to the linux kernel should be posted on the community forum at https://www.raspberrypi.org/forum (4.8.16).

    Can't seem to reproduce the problem and I now have a more up-to-date kernel :-).

    The problem is when I try and find the 1st version of 4.9.y with the problem I can't get any earlier than 4.9.10 as it doesn't have the necessary rpi specific patches (arch/arm/configs/bcm2709_defconfig) to compile.

    I'm trying a compile starting at 28cad4892910 (the earliest point in the rpi-4.9.y branch with this file) to see what happens, but it doesn't seem that much earlier than the 4.9.10-v7+ build I first tried which I already know has the issue.

    I did wonder about applying rpi patches to base 4.9 (69973b830859bc6529a) or maybe an earlier version, but that's beyond my git skills at present :-(.

    More than happy to add another remote to my git repo and give it a go if someone can publish a link...

    after running rpi-update on my box

    $ uname -a

    Linux pi2 4.9.30-v7+ #1001 SMP Fri May 26 16:09:18 BST 2017 armv7l ARMv7 Processor rev 5 (v7l) BCM2835 GNU/Linux

    Watching BBC2 HD the green artifacts are back (intermittently as they were before).

    Returning to the 4.8.16 build.

    Quote from metaron

    I'm confused. The current Rasbian 'official' Jesse image uses a 4.4 kernel. not 4.9.24. (Download Raspbian for Raspberry Pi)

    I'm guessing this is a more recent kernel downloaded using rpi-update. I'm giving this a go to see what happens.

    official image yes, but not if you update with "apt-get dist-upgrade)" there is 4.9.24.

    i can try with rpi-update as well... but as i said for me the raspbian build works fine...

    Quote from maroi

    official image yes, but not if you update with "apt-get dist-upgrade)" there is 4.9.24.

    i can try with rpi-update as well... but as i said for me the raspbian build works fine...

    Please confirm what "uname -a" reports when working fine and try rpi-update to see if it changes things.

    Your results and metaron's results don't match so it would be good to understand the discrepancy.

    Quote from metaron

    after running rpi-update on my box

    $ uname -a

    Linux pi2 4.9.30-v7+ #1001 SMP Fri May 26 16:09:18 BST 2017 armv7l ARMv7 Processor rev 5 (v7l) BCM2835 GNU/Linux

    Watching BBC2 HD the green artifacts are back (intermittently as they were before).

    Returning to the 4.8.16 build.

    sudo apt-get install --reinstall raspberrypi-bootloader raspberrypi-kernel

    should get you back to latest stable 4.9 kernel/firmware (i.e. matching marol). Could you double check if that is good/bad?

    Also maril/metaron are you using a Pi 3? Any non-default config.txt options?

    Might be interesting to make a list of USB DVB devices that have this problem (artefacts with 4.9 kernel but fine with 4.4 kernel).

    If you have this issue report make/model of device (a link to where it was obtained from may be useful).

    Output of "lsusb -v"

    OK, so now I'm really confused. I've blown a jesse-lite image to a spare SD card, logged in and run:

    sudo apt-get install --reinstall raspberrypi-bootloader raspberrypi-kernel

    but ls /lib/modules shows me 4.4.50+ 4.4.50-v7+ (which isn't the 4.9.24 version maroi says he has on his box)

    Typing sudo apt-get dist-upgrade tells me 0 upgraded, 0 newly installed, o to remove and 0 not upgraded. - so that doesn't work either.

    Looking through Commits · Hexxeh/rpi-firmware · GitHub I can't find a commit for 4.9.24 - it seems to skip directly from 4.9.23 to 4.9.25.

    I'm running gentoo on my pi2 and not familiar with the debian way of doing things (I was going to cut and paste the kernel onto my pi2 using tar)

    @marol - how did you get 4.9.24 on your rasbian box?

    Edit: Maybe kernel: Bump to 4.3.24 · Hexxeh/rpi-firmware@bbd611a · GitHub is it?

    (It's a bit late now - will try again another day!)

    Edited once, last by metaron (May 31, 2017 at 11:22 PM).

    Thank you for this interesting topic.

    I don't have any issues on my LibreElec system (still an older build, on a Intel x86-64 PC), but I have similar problems on one of my Raspberry Pi systems.

    I have a RPi2 installed with Raspbian Lite (CLI only), running TVHeadend (compiled form source) and using a DVBSky S960 as DVB-adapter.

    I use this setup only to record programs (on my NAS) and watch them afterwards on my TV or on the LibreElec system.

    Hence no need for LibreElec or Kodi or ... on my RPi2.

    The RPi2 has worked flawlessly for about 2 years, until it suddenly began to produce Continuity Counter Errors.

    To try and solve this, I tried the following things to no avail:

    * upgrade TVHeadend to the latest build
    * replace the RPi2 with another RPi2

    * replace the SD card and reinstall everything from scratch (re-downloaded raspbian image etc...)

    * swap the DVBSky S960 with an identical S960

    * replace the USB cable

    After reading this topic, I checked my RPi2 kernel and:

    pi@thuban:~ $ uname -a

    Linux thuban 4.9.24-v7+ #993 SMP Wed Apr 26 18:01:23 BST 2017 armv7l GNU/Linux

    So, I think I have the same issues, but even though I have a Linux 4.9 kernel and a DVBSky S960, I do not have LibreElec on this machine.

    Like someone else mentioned before, the Raspbian kernel is 4.4, yet mine is 4.9.24

    I do not recall upgrading the kernel on purpose, but it is possible it got upgraded during my install procedure.

    I do not have my notes at hand (at work), but I will try from scratch again with a vanilla Raspbian image and go from there.
    I have a good hope that staying away from 4.9 will solve my problem.

    I also hope this can help you to locate your problems, since mine has nothing to do with LibreElec itself but seems very similar if not the same.


    BTW:

    My other recording machines are Debian VMs on my ESXi-server in the basement. Since they all use an older kernel, they don't have this issue.

    (And that's where I got the other DVBSky adapter)

    gert@dziban:~$ uname -a

    Linux dziban 3.16.0-4-amd64 #1 SMP Debian 3.16.43-2 (2017-04-30) x86_64 GNU/Linux

    rpi-update using: kernel: Bump to 4.3.24 · Hexxeh/rpi-firmware@bbd611a · GitHub gives me:

    andrew@pi2 ~ $ uname -a
    Linux pi2 4.9.24-v7+ #991 SMP Sat Apr 22 20:26:57 BST 2017 armv7l ARMv7 Processor rev 5 (v7l) BCM2835 GNU/Linux

    Not quite what gert and maroi are running. Anyone know how to track down #993?

    Like you gert, I don't have LibreElec on the PI2 - I record using Mythv and then playback using LibreElec on a different machine (an RPi B+)

    (Mythtv always records to disk first, even if watching 'live')

    By the way I'm still seeing artifacts with build #991 on the PI2.

    Quote from gert

    The RPi2 has worked flawlessly for about 2 years, until it suddenly began to produce Continuity Counter Errors.

    If you want to narrow this down, can you back up your sdcard and try reverting the kernel.

    Code
    sudo rpi-update 7a47836821b92efa569500b3382b1812082e42d3

    will get you the last 4.8 kernel (4.8.13) which from my understanding should be good.

    Code
    sudo rpi-update bcc6146e102d85b1aa214855ad7aae278d3bd269

    will get you the first 4.9 kernel (4.9.0) which should have the problems.

    It would be useful if you (or others) can prove or disprove this is correct.

    Quote from metaron

    OK, so now I'm really confused. I've blown a jesse-lite image to a spare SD card, logged in and run:

    sudo apt-get install --reinstall raspberrypi-bootloader raspberrypi-kernel

    but ls /lib/modules shows me 4.4.50+ 4.4.50-v7+ (which isn't the 4.9.24 version maroi says he has on his box)

    Typing sudo apt-get dist-upgrade tells me 0 upgraded, 0 newly installed, o to remove and 0 not upgraded. - so that doesn't work either.

    Try running "apt-get update" beforehand to get the indexes up to date.

    Quote from popcornmix

    If you want to narrow this down, can you back up your sdcard and try reverting the kernel.

    Sure, no problem.

    No need to backup the card though. I am preparing a second RPi which I was planning to use anyway.

    I now have 2 RPIs which I can use for testing:

    * one is the original one, with kernel 4.9, and the continuity errors.

    * another one with a fresh raspbian image, currently at kernel 4.4


    The first one is the one with the continuity errors. It is not currently connected to the DVB-adapter but it is still on my network, so I can already prepare it:

    Code
    pi@thuban:/usr/local/etc $ uname -a
Linux thuban 4.9.24-v7+ #993 SMP Wed Apr 26 18:01:23 BST 2017 armv7l GNU/Linux

pi@thuban:/usr/local/etc $ sudo apt-get install rpi-update
pi@thuban:/usr/local/etc $ sudo rpi-update 7a47836821b92efa569500b3382b1812082e42d3
pi@thuban:/usr/local/etc $ sudo reboot

pi@thuban:~ $ uname -a
Linux thuban 4.8.13-v7+ #937 SMP Fri Dec 9 17:45:13 GMT 2016 armv7l GNU/Linux

    The TVHeadend install and config is still intact, so when I am back home and connect the DVBSky to it, I can start testing right away.


    The second one is a new install, which I planned to keep at 4.4 or 4.8

    That one is currently connected to the DVBSky. I was hoping to get the install of TVHeadend done during the breaks at workand have it up-and-running when I got home.

    That would give me a second chance of testing.

    Currently the kernel is still at 4.4

    Code
    pi@raspberrypi:~ $ uname -a
Linux raspberrypi 4.4.50-v7+ #970 SMP Mon Feb 20 19:18:29 GMT 2017 armv7l GNU/Linux

    I did not use rpi-update to update the kernel to 4.9, since I didn't even known that command before I read it here.

    I am fairly certain I just did apt-get update && apt-get upgrade (or maybe: apt-get dist-upgrade)


    I'll first check if I can make realiable recordings on both RPIs in the state they are in now (one reverted to 4.8, the other at 4.4) and then upgrade both to 4.9 to see what happens?

    Quote from gert

    I am fairly certain I just did apt-get update && apt-get upgrade (or maybe: apt-get dist-upgrade)

    That gets you the 4.9 kernel. The next raspbian sdcard image will use this kernel.
    (rpi-update currently gets a slightly newer 4.9 kernel and is the easiest way to downgrade to a previous kernel).