["Le Potato", LE 9.0.1] System crashs when playing a Full-HD/UHD video contained in an ISO independent of the chosen video player

1st Official Post

    Dear LibreELEC community,

    when taking a Libre Single-Board-Computer (SBC) "AML-S905X-CC" with 2GB RAM (Codename "Le Potato") having LibreELEC version 9.0.1 installed (complete re-flash of the internal SD-card) and trying to play a Full-HD/UHD video contained in an ISO file - independent of the chosen video player - the complete system crashes and hangs after >1-3 minutes. When choosing an UHD it happens earlier compared to a Full-HD. This effect can be reproduced each time - even when varying the file selection.

    Important: it seems not a memory leak as I checked the main memory using "top -o %MEM" (sorting "%mem" descending) during the video playback. For me, it seems to be a problem with "ffmpeg" version 4.0.3 used in this Kodi/LibreELEC version. Current version is ffmpeg 4.1.1

    The below table shows the requested informations needed for a bug report:

    Key Value
    Hardware Specs Libre Computer Board AML-S905X-CC with 2GB RAM, Codename Le Potato
    LibreELEC version 9.0.1 (libreelec-lepotato.arm-9.0.1.img.gz)
    Debug log
    		 kodi.log (created via: "tail -f -n10000 /storage/.kodi/temp/kodi.log)
    dmesg.log (created via: "dmesg" once before the crash happened)

    Hints:
    - the crash happens a few seconds later compared to the last timestamp mentioned in "kodi.log"
    Reproduction description
    		 Download the DEMO UHD video and package it in an ISO file created with ImgBurn. Store it on a harddisk and attach this harddisk via USB to the SBC "Le Potato".

    Boot LibreELEC 9.0.1 on "Le Potato" -> Settings -> File Manager -> Select the harddisk attached to one of the four USB ports -> Navigate to a folder where a UHD or Full-HD encoded ISO file is stored -> via the context menu either choose the standard or non-standard video player -> wait until the crash appears

    Hints:
    - the boot loader has not been updated to get rid of the bug mentioned here!
    - after the crash, the SSH session freezes and gets disconnected
    Kodi video and audio settings: Audio settings (Settings -> System):
    Audio    : [Audio Decoder: Audio output device: ALSA: Default (AML-M8AUDIO Analog); Number of channels: 2.0; Volume control steps: 20], [GUI Sounds: Play GUI sounds: Only when playback stopped; GUI sounds: Kodi UI Sounds], [Audio Passthrough: Allow passthrough: disabled; Passthrough output device: ALSA: AML-M8AUDIO, HDMI]

    Player settings (Settings -> Player):
    Videos: [Actions: Skip steps: -10min, -5min, -3 min, -60 sec, -30sec, -10sec, 10sec, 30sec, 60sec, 3min, 5min, 10min; Skip delay: 750ms]; [Playback: Adjust display refresh rate: Off; Sync playback to display: disabled]
    Discs: [DVD: Play DVDs automatically, Forced DVD player region], [Blu-ray: Blu-ray region Code: Region B; Blu-ray playback mode: Play main movie], [Audio CDs: Audio CD insert action: None; Load audio CD information from online service: enabled]
    Language: [Audio: Preferred audio language: German; Prefer default audio streams: enabled], [Subtitles: Preferred subtitle language: Original language; Enable parsing for closed captions: disabled; Font to use for text subtitles: arial.ttf; Character set: Default], [Download Services: Languages to download subtitles for: English; Default TV show service: None; Default movie service: None]
    Media info:
    		 LG Cymatic Jazz is a promotional video, in HDR HLG Ultra-HD, for LG 4K TVs.
    LG: Cymatic Jazz HDR HLG UHD 4K Demo | 4K Media

    Video Info: Resolution : 3840 x 2160
    File size : 738 MB
    Duration : 00:04:58
    Format : MP4
    Codec : HEVC
    Overall bit rate : 61,8 Mb/s
    Bit depth : 10 bits
    Frame rate : 60 fps

    Maybe this problem is already well known - or may solved in one of the nightly builds?

    Edited 26 times, last by diego (March 2, 2019 at 4:01 PM).

    The root cause for the system crash/hang/freezes during the playback of a video nested in an ISO file seems to be located in a segmentation fault. A possible solution is to use a patched "booloader.img" for LibreELEC!

    When switching to CoreELEC 9.0.1 the problem has gone as the community there might have already integrated the correct bootloader in that version.

    Is there a chance to come back to LibreELEC by preventing the segmentation fault with a fixed "bootloader.img" in LibreELEC, too?

    Edited 2 times, last by diego (March 30, 2019 at 6:04 AM).

    If this helps: I'm not sure where the real issue is but I attacked it a little differently. I too had the freezing and lockups and I tried the above with no success and was about to give up but I had the thought that I wished I had a working build of LE that could apply to the Le Potato and just mod it to work. Then I realized I have a Khadas VIM with the same 905x cpu same gpu and amount of memory, but some variance in other hardware. I remembered that after 8.2 the dtb.img file was provided and different for most builds and available in most of the install images. Needless to say I configured my VIM the way I wanted it got everything working then cloned the SD card to another for the Potato afterwards I changed the dtb.img file over to the Le Potato version and to my surprise everything works and I have yet to get any lockups or freezing as before from a fresh build.

    I'm not sure what the difference is, I'm not that good to identify what changed. All I know is whenever I tried to deal with higher end video, install something like widevine for Netflix/Prime Video it would crash it using a fresh official install for Le Potato. However for some reason now it handles those more intensive operations just fine so something is different.

    If someone could educate me on how to compress/shrink the size of that clone image to actual data size (instead of a 32g disk image) I would gladly share this working version for the Potato for anyone that needs it. Edit: I was able to shrink it to 1.7g, but I can certainly get it smaller it I eliminate some unnecessary items.

    I did try Coreelec on this device and it had even more issues beyond the freezing and lockups so I stuck with LE, but this is not the forum for that.

    Edited 2 times, last by schmittty: Edit: I was able to shrink it to 1.7g, but I can certainly get it smaller it I eliminate some unnecessary items. (May 2, 2019 at 2:31 PM).