Comment # 18 on bug 1004052 from Takashi Iwai

Thanks for the updated information.  OK, then the fix for dell_wmi is basically
irrelevant with the workqueue things.

Through a quick glance, I couldn't find any relevant change in dell-laptop
driver code itself, but a dcdbas driver change might be relevant.
Unfortunately that dcdbas change can't be applied to 4.4.x cleanly (due to the
new API).

So, another try is to revert a change in dell_laptop driver.  I changed
dell_laptop kmp now, so try it later once when the build finishes.  (Check the
changelog.)