GPU HANG + segfault in libflashplayer.so

[i-rinat]

GPU HANG + segfault in libflashplayer.so

[i-rinat]

(Just to be sure.) Browser plugin crashes after you launch mpv? If so, cause must be somewhere in common part. First thought — a kernel driver issue. Or maybe Xorg.

Although there is another possibility. GPU decoding is quite fragile when it gets a damaged input. I saw a lot of both temporary and permanent hangs during development when I fed VA-API driver with a wrong input. In latter case I needed to power off machine and the start again to get it working. So if there is something wrong with libvdpau-va-gl parsing code (actually, it's wrong, as part of H.264 parser was never written), it may leave GPU in a wrong state. However issue would not appear recently, because I didn't change the code for a long time.

[i-rinat]

I also saw crashes in intel GL driver, and thought there're bug in that driver, but later found that I have a bug in my code. So it's worth to try to run plugin under Valgrind. There is a trick (link) which helps to run only plugin-container under Valgrind rather than the whole browser.

[duud]

Yes, it crashes after launching mpv.
GPU decoding ist disabaled, It stoped working for me recently (EnableLinuxHWVideoDecode=0) , I only use libvdpau-va-gl for accelerated rendereing. (btw. i don't know why accelerated rendering isn't working without libvdpau-va-gl, I think you have more insight here, so do you know why?)

[i-rinat]

why accelerated rendering isn't working without libvdpau-va-gl

The only known hardware accelerated way to output graphics and decode video for Flash 11.2 is VDPAU. It doesn't use platform's OpenGL, therefore without working VDPAU driver Flash falls back to all-software mode.

[duud]

Ok thx.

I never used valgrind, it would be nice if you have some time to take a look:
http://expirebox.com/download/81bfce0e26e68ebcac3653416144ecca.html

[duud]

Your intuition was right.
Recently arch updated mesa from 10.5.7 to 10.6.0.
I installed 10.5.7, accelerated rendering + decoding is working properly again.

[i-rinat]

take a look

I see nothing wrong there. Multiple use-after-free warnings are due to quirks in glib2.0 code.

[duud]

Thank you.

This is not related but you're the right person to ask :)
Are there any reasons/advantages for using freshplayerplugin+pepperflash?

[i-rinat]

Are there any reasons/advantages for using freshplayerplugin+pepperflash?

During libvdpau-va-gl development I found that NPAPI Flash uses VDPAU only when wmode parameter is equal to either window or direct. It's the case on Youtube, so it's fine there. But many other sites with other players, and even some embedded videos from Youtube are using wmode=transparent or wmode=opaque, thus forcing Flash to use CPU for all rendering.

To support transparency, NPAPI Flash uses different modes, windowed and windowless. In first case plugin either creates or receives an X Window which it draws at. In second case (windowless), browser creates Pixmaps where plugin paint. Windowless operation mode is required for transparency — browser passes Pixmap already with content, and plugin paints over it. That mode is also required if one wants to paint over plugin instance, display a text, for example, or custom HTML controls. But since with windowless mode one doesn't have a known Window, using of VDPAU is hard, if even possible. That's why Flash falls back to software rendering.

I once thought about creating a proxy plugin to make Flash believe that it always can use VDPAU, but decided to make such proxy for PepperFlash after all. Since I do all the interaction with OS and browser, I'm able to allow Flash to use hardware accelerated rendering regardless of plugin mode.

At the end of the day, freshwrapper can help reduce CPU load, moving some of it to GPU. Or maybe not. It depends. I also heard some people use it where Flash 11.5 is required, and therefore 11.2 doesn't work.

[duud]

Very detailed answer, nice.
This information is really usefull so I think it should be put into freshplayerplugin's readme.
Just put a link to your previous post, it's pretty detailed.