Cantabile, please give these patches a spin and let me know if it fixes
your reported issue. They depend on other pending patches I have in line
waiting to be merged so the easiest I thing I think is for you to test my
20180227-firmware-cache branch [0], based on Linus' tree. To get that
tree, cd into your Linus git tree and do:
git remote add mcgrof https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git
git checkout -b 20180227-firmware-cache mcgrof/20180227-firmware-cache
Please let me know if this resolves your issue and thanks for your report.