Comment 131 for bug 1275794

I tried applying the patch ([PATCH]HDMI connection via dock works with some (random) delay: https://bugs.freedesktop.org/attachment.cgi?id=93653) against a 3.13 kernel, and it makes things **worse** on my T540p. With the 3.13 kernel w/o the patch, I can boot and start up the X server w/o problems, as long as it is not docked. With this patch, the system locks up very early in the boot process, as soon as the console switches from the compat VGA mode into the higher resolution console mode).

Also, when comparing an unpatched 3.12 kernel with an unpatched 3.13 kernel, 3.13 is also worse with the T540p. With the unpatched 3.12 kernel, I can have the laptop in the dock, and so long as there are no external monditors hooked up via the dock video connectors, it worked fine. With the unpatched 3.13 kernel, it's fine outside of the dock, but if it is in the dock, even if the dock does not have any external video monitors hooked up, any time there is any change to the video setup (i.e., X server starts up, DPMS puts the monitor to sleep, etc.) the system will lock up. It will recover after I eject the laptop from the dock, and after that point I can redock it, but while the system is locked up, the laptop heats up and the fan starts up --- which I suspect means that we are indeed hanging in some spinlock.