X Video finally works - Poulsbo and Linux on the MSI Wind U110 - Fix for BUG: kernel NULL pointer dereference at 00000000

If you tried to get poulsbo to run on your system and you get a message like this, you should try the fix posted below.

"kernel BUG: unable to handle kernel NULL pointer dereference at 00000000" (2.6.28)
"kernel BUG: unable to handle kernel NULL pointer dereference at (null)" (2.6.31)

Thanks to a post on Ubuntu's bugzilla, the poulsbo video module now finally works on my MSI Wind U110 (full review & installation guide). Download the psb-kernel-source module You only have to comment out the two lines in intel_lvds.c starting with

if (edid)
....

e.g.
/* if (edid)
drm_add_edid_modes(output, edid); */

Then reconfigure the package and it should be recompiled. The next time you start it, it should work instead of creating kernel BUG

Update:
Xvideo actually works better than in Directx video in Windows XP, where I often see blocky video scaling. The CPU usage is not too high, either. Currently it's only working under Ubuntu 9.04 for me. Though I had managed to compile the module with kernel 2.6.30 before, I don't remember how I did that... And I haven't gotten actual video acceleration to work yet.

Of course I'll keep you updated and I'll post a little howto once it's all working. But feel free to ask, anyway. And thanks so much to the person from the Ubuntu bugzilla who helped me to finally get it all working!!!

Update2: Keep checking the page. I will post a link to an archive with a script that will manage the compilation in Ubuntu 9.10. If someone could help me figure out how to, I'd love to create, upload and post a .deb for dkms so it all works automatically... Or ultimately, we could modify the driver to check for the MSI's signature and then skip the edid check.

I've created a package for Karmic that you can use to manually install the driver with the fix already applied: http://www.megaupload.com/?d=BB23R7K2. Extract it and execute the script make_psb.sh, then reboot and try to modprobe psb. Let me know when the 10 downloads run out and it it works for you.

Update3: Here is a step by step howto. It explains setting up X and then VAAPI (hardware video decoding) in Kubuntu 9.10.

My script for making the psb module out of the package:

KERNEL=/lib/modules/`uname -r`/
make KERNELRELEASE="$(uname -r)" LINUXDIR="/lib/modules/$(uname -r)/build" DRM_MODULES=psb || exit 1;
sudo cp drm.ko $KERNEL/kernel/drivers/gpu/drm/drm.ko
sudo mkdir -p $KERNEL/updates/dkms
sudo cp psb.ko $KERNEL/updates/dkms/psb.ko
ls -l $KERNEL/kernel/drivers/gpu/drm/drm.ko $KERNEL/updates/dkms/psb.ko
sudo depmod -a

9 comments:

  1. Does this need any additional packages (e.g. from the PPAs) or is the tar.bz2 everything that is needed?

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  2. to answer myself: it seems as if the tar.bz2 is actually everything that is needed.
    I just did a clean install of ubuntu 9.10 on my MSI Wind U115 hybrid. When doing a sudo modprobe psb after an install, I can see the following in dmesg:
    error: psb: no valid msvdx_fw.bin firmware found

    The Framebuffer seems to work fine afterwards, but X is broken (I see my mouse pointer moving about 4 times and there is a lot of garbage on the screen, can't really see anything)

    But that's further than I ever came before :)

    Thanks!

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  3. Hi Marc,

    you're very welcome. If you want to really get it working, try installing the review&installation guide: http://linux-tipps.blogspot.com/2009/08/msi-wind-u110-linux-review.html.
    At the bottom it describes how to get X runnig completely. Once that's done, there is also a link how to get VAAPI acceleration working. Please keep in touch and post your results. I'm especially interested how low you can get your power consumption (http://linux-tipps.blogspot.com/2009/12/over-9-hours-of-video-on-battery-with.html) with the U115 (powertop).
    Good luck and talk to you soon!

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  4. This comment has been removed by the author.

    ReplyDelete
  5. okay. This is the real link for the how to of setting up X and VAAPI:
    http://linux-tipps.blogspot.com/2009/12/vaapi-accelerated-hd-video-on-msi-wind.html

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  6. The Rapidshare link is not yet available....

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  7. Any chance of getting that script uploaded again?

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  8. Do you mean this script?

    KERNEL=/lib/modules/`uname -r`/
    make KERNELRELEASE="$(uname -r)" LINUXDIR="/lib/modules/$(uname -r)/build" DRM_MODULES=psb psb.o || exit 1;
    sudo cp drm.ko $KERNEL/kernel/drivers/gpu/drm/drm.ko
    sudo mkdir -p $KERNEL/updates/dkms
    sudo cp psb.ko $KERNEL/updates/dkms/psb.ko
    ls -l $KERNEL/kernel/drivers/gpu/drm/drm.ko $KERNEL/updates/dkms/psb.ko
    sudo depmod -a

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  9. I've uploaded the file to megaupload now. Keep downloading or it will be deleted again eventually... :/
    If someone is willing to host it feel free and post a link.

    ReplyDelete

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