Can you double check you are using a build from git? There was an issue with dri3 being incorrectly detected that resulted in that error.

Could you please run "intel-virtual-output -v" and attach the output, and also the output of xtrace intel-virtual-output?

(In reply to Chris Wilson from comment #1)
> Can you double check you are using a build from git? There was an issue with
> dri3 being incorrectly detected that resulted in that error.
> 
> Could you please run "intel-virtual-output -v" and attach the output, and
> also the output of xtrace intel-virtual-output?

Ouch. I had built it, but apparently forgot to copy it into `/usr/local/bin/` and since there was an older version in there, I didn't notice...

Can't believe it was for something that stupid. Anyway, thanks a lot for noticing that, works like a charm now!

(I'm not used to this bug-tracker, could you close it as invalid please?)

It *was* a valid bug :)

*** This bug has been marked as a duplicate of bug 89172 ***

intel-virtual-output: version 2.99.917
display_open((null))
:0: has_shm?=1, event=65, opcode=130, has_pixmap?=1
:0: randr_active?=1, event=89, error=147
:0: xinerama_active?=1, event=0, error=0
:0: dri3_active?=0
XIO:  fatal IO error 11 (Resource temporarily unavailable) on X server ":0"
      after 20 requests (20 known processed) with 0 events remaining.

output of xtrace intel-virtual-output :-

luffy@luffy:~$ xtrace intel-virtual-output
No display name to create specified, trying :9
Got connection from unknown(local)
000:<: am lsb-first want 11:0 authorising with 'MIT-MAGIC-COOKIE-1' of length 16
000:>: Success, version is 11:0 vendor='The X.Org Foundation' release=11701000 resource-id=0x04000000 resource-mask=0x001fffff motion-buffer-size=256 max-request-len=65535 image-byte-order=LSBFirst(0x00) bitmap-bit-order=LeastSignificant(0x00) scanline-unit=32 scanline-pad=32 min-keycode=0x08 max-keycode=0x00 pixmap-formats={depth=1 bits/pixel=1 scanline-pad=32},{depth=4 bits/pixel=8 scanline-pad=32},{depth=8 bits/pixel=8 scanline-pad=32},{depth=15 bits/pixel=16 scanline-pad=32},{depth=16 bits/pixel=16 scanline-pad=32},{depth=24 bits/pixel=32 scanline-pad=32},{depth=32 bits/pixel=32 scanline-pad=32}; roots={root=0x000000a0 default-colormap=0x00000022 white-pixel=0x00ffffff black-pixel=0x00000000 input-mask=KeyPress,KeyRelease,ButtonPress,ButtonRelease,EnterWindow,LeaveWindow,Exposure,StructureNotify,SubstructureNotify,SubstructureRedirect,FocusChange,PropertyChange width[pixel]=1366 height[pixel]=768 width[mm]=361 height[mm]=203 min-installed-maps=1 max-installed-maps=1 root=0x00000020 backing-stores=WhenMapped(0x01) save-unders=false(0x00) root-depth=24 allowed depths={depth=24 visuals={id=0x00000020 class=TrueColor(0x04) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x00000021 class=DirectColor(0x05) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x00000092 class=TrueColor(0x04) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x00000093 class=TrueColor(0x04) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x00000094 class=TrueColor(0x04) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x00000095 class=TrueColor(0x04) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x00000096 class=TrueColor(0x04) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x00000097 class=TrueColor(0x04) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x00000098 class=DirectColor(0x05) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x00000099 class=DirectColor(0x05) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x0000009a class=DirectColor(0x05) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x0000009b class=DirectColor(0x05) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x0000009c class=DirectColor(0x05) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x0000009d class=DirectColor(0x05) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff},{id=0x0000009e class=DirectColor(0x05) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff};},{depth=1 visuals=;},{depth=4 visuals=;},{depth=8 visuals=;},{depth=15 visuals=;},{depth=16 visuals=;},{depth=32 visuals={id=0x0000006d class=TrueColor(0x04) bits/rgb-value=8 colormap-entries=256 red-mask=0x00ff0000 green-mask=0x0000ff00 blue-mask=0x000000ff};};};
000:<:0001: 20: Request(98): QueryExtension name='BIG-REQUESTS'
000:>:0001:32: Reply to QueryExtension: present=true(0x01) major-opcode=133 first-event=0 first-error=0
000:<:0002:  4: BIG-REQUESTS-Request(133,0): Enable 
000:>:0002:32: Reply to Enable: maximum-request-length=4194303
000:<:0003: 20: Request(55): CreateGC cid=0x04000000 drawable=0x000000a0 values={background=0x00ffffff}
000:<:0004: 24: Request(20): GetProperty delete=false(0x00) window=0x000000a0 property=0x17("RESOURCE_MANAGER") type=0x1f("STRING") long-offset=0x00000000 long-length=0x05f5e100
000:>:0004:140: Reply to GetProperty: type=0x1f("STRING") bytes-after=0x00000000 data='*customization:\t-color\nXft.dpi:\t96\nXft.antialias:\t1\nXft.hinting:\t1\nXft.hintstyle:\thintslight\nXft.rgba:\trgb\n'
000:<:0005: 20: Request(98): QueryExtension name='XKEYBOARD'
000:>:0005:32: Reply to QueryExtension: present=true(0x01) major-opcode=135 first-event=85 first-error=137
000:<:0006:  8: XKEYBOARD-Request(135,0): UseExtension major=1 minor=0
000:>:0006:32: Reply to UseExtension: major=1 minor=0
000:<:0007: 16: Request(98): QueryExtension name='MIT-SHM'
000:>:0007:32: Reply to QueryExtension: present=true(0x01) major-opcode=130 first-event=65 first-error=128
000:<:0008: 32: Request(98): QueryExtension name='Generic Event Extension'
000:>:0008:32: Reply to QueryExtension: present=true(0x01) major-opcode=128 first-event=0 first-error=0
000:<:0009:  8: Generic Event Extension-Request(128,0): QueryVersion major version=1 minor version=0
000:>:0009:32: Reply to QueryVersion: major version=1 minor version=0
000:<:000a:  4: MIT-SHM-Request(130,0): QueryVersion 
000:>:000a:32: Reply to QueryVersion: major-version=1 minor-version=2 uid=0 gid=0 pixmap-format=ZPixmap(0x02)
000:<:000b:  4: Request(43): GetInputFocus 
000:>:000b:32: Reply to GetInputFocus: revert-to=Parent(0x02) focus=0x0340000c
000:<:000c: 16: MIT-SHM-Request(130,1): Attach shmseg=0x04000001 shmid=0x001a000a readonly=false(0x00)
000:<:000d:  4: Request(43): GetInputFocus 
000:>:000d:32: Reply to GetInputFocus: revert-to=Parent(0x02) focus=0x0340000c
000:<:000e: 16: Request(98): QueryExtension name='MIT-SHM'
000:>:000e:32: Reply to QueryExtension: present=true(0x01) major-opcode=130 first-event=65 first-error=128
000:<:000f: 44: Request(25): SendEvent propagate=false(0x00) destination=0x000000a0 event-mask=0 (generated) MIT-SHM-Completion(65) drawable=0x000000a0 shmseg=0x001a000a offset=0x00000000
000:<:0010:  4: Request(43): GetInputFocus 
000:>:0010:32: Reply to GetInputFocus: revert-to=Parent(0x02) focus=0x0340000c
000:<:0011:  8: MIT-SHM-Request(130,2): Detach shmseg=0x04000001
000:<:0012: 16: Request(98): QueryExtension name='RANDR'
000:>:0012:32: Reply to QueryExtension: present=true(0x01) major-opcode=140 first-event=89 first-error=147
000:<:0013: 16: Request(98): QueryExtension name='XINERAMA'
000:>:0013:32: Reply to QueryExtension: present=true(0x01) major-opcode=141 first-event=0 first-error=0
000:<:0014:  4: XINERAMA-Request(141,4): IsActive 
000:>:0014:32: Reply to IsActive: state=true(0x00000001)
000:<:0015: 12: Request(98): QueryExtension name='DRI3'
000:>:0015:32: Reply to QueryExtension: present=false(0x00) major-opcode=0 first-event=0 first-error=0
XIO:  fatal IO error 11 (Resource temporarily unavailable) on X server ":9"
      after 20 requests (20 known processed) with 0 events remaining.