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Sometimes while running apps using OpenGL, the following message comes in the command line where I run the app. I have a Sandy Bridge integrated graphics card (the same as in the bug reports)

intel_do_flush_locked failed: Input/output error

Running any subsequent OpenGL apps fail with the same error. Also this is displayed in the system log

[ 7730.683403] [drm:i915_wait_request] *ERROR* i915_wait_request returns -11 (awaiting 1322416 at 1322415, next 1322417)

I have seen many bugs about this but none of them seem to have a solution. Is there any workaround for this (apart from disabling OpenGL)?

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Try LIBGL_ALWAYS_SOFTWARE=1 ./yourprogram

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This is a work-around at best. – David Foerster Sep 12 '15 at 10:15

The following seems to fixed the issue for me:

export hiz=false
export INTEL_HIZ=0

If it doesn't help try

sudo intel_reg_write 0x2120 0x1206800


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I've changed my computer; so I can't test it but I'm upvoting. – Ramchandra Apte Mar 4 '14 at 13:56
@RamchandraApte I think You shouldn't than. – Adobe Mar 4 '14 at 14:02
Doesn't help. Anything else to try? – temoto Jan 25 '15 at 21:24
According to the source of this fix, this helps only with kernels before 3.3, after that the kernel fixes the problem. Did not help me, but I only get the intel_do_flush_locked failed message, not the syslog entry. – Trendfischer Apr 17 '15 at 18:40

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