I have a Lenovo ThinkPad t430i with a dock. The dock has one DVI and DisplayPort connector each. When using kernel 3.10, I use all three displays. However, after upgrading to linux 3.11, the DVI connected monitor will only enter sleep mode when connected (from either non-X tty or when X is running). uname -srvmo: Linux 3.11.2-1-ARCH #1 SMP PREEMPT Fri Sep 27 07:35:36 CEST 2013 x86_64 GNU/Linux Output from xrandr shows that all three displays are present, but I receive "xrandr: Configure crtc 2 failed" when I try to manipulate the DVI output: Screen 0: minimum 320 x 200, current 3046 x 1050, maximum 32767 x 32767 LVDS1 connected 1366x768+1680+0 (normal left inverted right x axis y axis) 309mm x 173mm 1366x768 60.1*+ 1024x768 60.0 800x600 60.3 56.2 640x480 59.9 VGA1 disconnected (normal left inverted right x axis y axis) HDMI1 disconnected (normal left inverted right x axis y axis) DP1 disconnected (normal left inverted right x axis y axis) HDMI2 connected 1680x1050+0+0 (normal left inverted right x axis y axis) 473mm x 296mm 1680x1050 60.0*+ 1600x1200 60.0 1280x1024 60.0 1440x900 59.9 1280x960 60.0 1024x768 60.0 800x600 60.3 640x480 60.0 720x400 70.1 HDMI3 connected (normal left inverted right x axis y axis) 1680x1050 60.0 + 1600x1200 60.0 1280x1024 60.0 1440x900 59.9 1280x960 60.0 1024x768 60.0 800x600 60.3 640x480 60.0 720x400 70.1 DP2 disconnected (normal left inverted right x axis y axis) DP3 disconnected (normal left inverted right x axis y axis) lspci -vv shows: 00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09) (prog-if 00 [VGA controller]) Subsystem: Lenovo Device 21f3 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin A routed to IRQ 48 Region 0: Memory at f0000000 (64-bit, non-prefetchable) [size=4M] Region 2: Memory at e0000000 (64-bit, prefetchable) [size=256M] Region 4: I/O ports at 5000 [size=64] Expansion ROM at <unassigned> [disabled] Capabilities: <access denied> Kernel driver in use: i915 Kernel modules: i915 Please let me know what other information is helpful. Thank you.
We have a bunch of bug reports all to the same effect. Everyone confirmed that the latest drm-intel-nightly kernel from http://cgit.freedesktop.org/~danvet/drm-intel/ seems to restore 3 pipe on ivb, but unfortunately no one yet bothered to do the reverse bisect so that we can fix 3.11 kernels :( I can't repro the bug, so I can't really help ...
Is there documentation on the reverse bisection procedure so I can see if it's something I could assist in? I'm new (I created a bugzilla account for this bug), but I'm spoiled enough by my triple monitor setup that I'd be willing to put in some effort to help push this issue along.
The ubuntu wiki has a nice kernel bisect howto with a section about reverse bisecting (i.e. figuring out which commit fixed something as opposed to broke something, which is not entirely a symmetric problem). Hopefully that should get you started: https://wiki.ubuntu.com/Kernel/KernelBisection (The first part is about bisecting ubunut kernels, you can skip all that)
Status update: I'm in the process of running a bisect, but I'm encountering an issue: For some commits, I see no disk activity after the two lines stating "Loading kernel" and "Loading initramfs" (paraphrased, mind you). While I'm glad later commits appear to have addressed this issue, hopefully the "breaking" commit isn't in the range where I cannot even boot the kernel image.
Matthew, can you confirm that later kernels work for you? 3.11 is no longer supported.
Closing, please reopen if the problem persists with newer kernels.
Sorry for the late response. Later kernels fixed this just fine.