Comment 37 for bug 1308674

I see the following stacktrace after suspending/resuming and undocking:

[74755.531008] Hardware name: LENOVO 4243BQ9/4243BQ9, BIOS 8AET56WW (1.36 ) 12/06/2011
[74755.531010] 0000000000000009 ffff8800ca74dbd0 ffffffff81686fdc ffff8800ca74dc18
[74755.531015] ffff8800ca74dc08 ffffffff8106d47d ffff880036ce8000 0000000000070008
[74755.531018] 00000001046fce31 0000000000000000 ffff88021029a320 ffff8800ca74dc68
[74755.531022] Call Trace:
[74755.531033] [<ffffffff81686fdc>] dump_stack+0x45/0x56
[74755.531040] [<ffffffff8106d47d>] warn_slowpath_common+0x7d/0xa0
[74755.531045] [<ffffffff8106d4ec>] warn_slowpath_fmt+0x4c/0x50
[74755.531071] [<ffffffffa00cc2cb>] intel_wait_for_pipe_off+0x1db/0x1f0 [i915]
[74755.531093] [<ffffffffa00cc380>] intel_disable_pipe+0xa0/0xb0 [i915]
[74755.531114] [<ffffffffa00cd454>] ironlake_crtc_disable+0xe4/0x940 [i915]
[74755.531135] [<ffffffffa00d3abf>] intel_crtc_update_dpms+0x6f/0xa0 [i915]
[74755.531157] [<ffffffffa00d7429>] intel_connector_dpms+0x59/0x70 [i915]
[74755.531180] [<ffffffffa003b3f8>] drm_mode_obj_set_property_ioctl+0x328/0x340 [drm]
[74755.531199] [<ffffffffa003b440>] drm_mode_connector_property_set_ioctl+0x30/0x40 [drm]
[74755.531214] [<ffffffffa002ab52>] drm_ioctl+0x502/0x630 [drm]
[74755.531226] [<ffffffff8119d2bf>] ? kfree+0xff/0x130
[74755.531231] [<ffffffff81321b50>] ? lockref_put_or_lock+0x50/0x80
[74755.531236] [<ffffffff811cb6d8>] do_vfs_ioctl+0x2d8/0x4a0
[74755.531241] [<ffffffff811ba77e>] ? ____fput+0xe/0x10
[74755.531244] [<ffffffff811cb921>] SyS_ioctl+0x81/0xa0
[74755.531250] [<ffffffff81695fa9>] system_call_fastpath+0x16/0x1b
[74755.531253] ---[ end trace cd788d6e38c5424a ]---
[74755.582844] [drm:ironlake_disable_pch_transcoder] *ERROR* failed to disable transcoder A

This clearly worked with 3.12