There's another thread where switching to uxa fixed the hangs - yeah, lots of threads about Intel GPU hangs lately . But that doesn't mean sna is the problem, I still say the kernel is the problem, sna merely uses the GPU in a way that exposes the issue. Try sna again once the 4.3 kernel is released, it fixed the issues I was having.
I can confirm that changing from SNA to UXA helps.
https://bbs.archlinux.org/viewtopic.php?id=202938
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Oooops! too late
[ 69.057154] [drm] GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.
switching to uxa it's worth a try .
]]>It's been my experience that the 4.1 and 4.2 kernels are quite bad for intel graphics, I've had several hangs every day on an Ironlake machine. The 4.3-rc kernel has been very solid though. I would advise you to try the linux-lts kernel, but LTS is now 4.1, so... yeah . Try it anyway, might work better.
]]>-EDIT-
Intel video driver hung or was unusable on 845g for a long period of time in the past (I had one...), until they fixed it in late 2012.
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Now every time i try to play video in vlc this happens
dmesg: [ 2140.168617] vlc[1833]: segfault at a92bc070 ip b7616fb0 sp a8a05e58 error 6 in libc-2.22.so[b74ed000+1b3000]
what's happining
i turned off acelerated video playback in vlc now this happens:
[ 2387.101281] vlc[1941]: segfault at 9cdf3001 ip a12f1510 sp a789bc00 error 4 in i915_dri.so[a126c000+641000]