When I run a kernel or NVIDIA driver update on my 16.04, this triggers an initramfs rebuild which outputs the warning below:
Processing triggers for initramfs-tools (0.122ubuntu8.1) ...
update-initramfs: Generating /boot/initrd.img-4.4.0-34-generic
W: Possible missing firmware /lib/firmware/i915/skl_guc_ver6.bin for module i915_bpo
I have a notebook with two graphics chips, an NVIDIA GeForce 940M and the Intel i5-6200U's integrated graphics.
The device in use is my NVIDIA card:
$ inxi -G
Graphics: Card-1: Intel Sky Lake Integrated Graphics
Card-2: NVIDIA GM108M [GeForce 940M]
Display Server: X.Org 1.18.3 driver: nvidia Resolution: 1920x1080@60.03hz
GLX Renderer: GeForce 940M/PCIe/SSE2 GLX Version: 4.5.0 NVIDIA 367.35
Here's the output of lshw -c video, corresponding to my Intel graphics chip which should use that driver:
*-display
description: VGA compatible controller
product: Sky Lake Integrated Graphics
vendor: Intel Corporation
physical id: 2
bus info: pci@0000:00:02.0
version: 07
width: 64 bits
clock: 33MHz
capabilities: pciexpress msi pm vga_controller bus_master cap_list rom
configuration: driver=i915_bpo latency=0
resources: irq:125 memory:a2000000-a2ffffff memory:b0000000-bfffffff ioport:5000(size=64)
The file in the warning does not exist, only those:
$ ll /lib/firmware/i915/
total 336
drwxr-xr-x 2 root root 4096 Aug 11 13:24 ./
drwxr-xr-x 74 root root 32768 Aug 11 13:24 ../
-rw-r--r-- 1 root root 5872 Jul 21 17:03 bxt_dmc_ver1_04.bin
-rw-r--r-- 1 root root 5872 Jul 21 17:03 bxt_dmc_ver1_05.bin
-rw-r--r-- 1 root root 8380 Jul 21 17:03 bxt_dmc_ver1_06.bin
-rw-r--r-- 1 root root 8380 Jul 21 17:05 bxt_dmc_ver1_07.bin
lrwxrwxrwx 1 root root 19 Jul 21 17:05 bxt_dmc_ver1.bin -> bxt_dmc_ver1_07.bin
-rw-r--r-- 1 root root 8824 Jul 21 17:03 skl_dmc_ver1_23.bin
-rw-r--r-- 1 root root 8928 Jul 12 21:33 skl_dmc_ver1_26.bin
lrwxrwxrwx 1 root root 19 Jul 12 21:33 skl_dmc_ver1.bin -> skl_dmc_ver1_26.bin
-rw-r--r-- 1 root root 109636 Jul 21 17:03 skl_guc_ver1_1059.bin
lrwxrwxrwx 1 root root 21 Jul 21 17:03 skl_guc_ver1.bin -> skl_guc_ver1_1059.bin
-rw-r--r-- 1 root root 128320 Jul 21 17:03 skl_guc_ver4_3.bin
lrwxrwxrwx 1 root root 18 Jul 21 17:03 skl_guc_ver4.bin -> skl_guc_ver4_3.bin
The latest driver package seems to be installed though:
$ apt-cache policy xserver-xorg-video-intel
xserver-xorg-video-intel:
Installed: 2:2.99.917+git20160325-1ubuntu1
Candidate: 2:2.99.917+git20160325-1ubuntu1
Version table:
*** 2:2.99.917+git20160325-1ubuntu1 500
500 http://ftp.uni-stuttgart.de/ubuntu xenial/main amd64 Packages
100 /var/lib/dpkg/status
What does this warning mean exactly and how can I fix it?




W: Possible missing firmware /lib/firmware/i915/kbl_dmc_ver1.bin for module i915_bpoand my CPU is SKylake with Intel HD in it. – Csaba Toth Oct 15 '16 at 17:201.158version of thelinux-firmwarepackage instead of the mainline1.157because only that provided working firmware for my wifi (killer wireless). – Csaba Toth Oct 15 '16 at 17:24kblstands for Kabylake, which is the successor of Skylake. As you don't have such a CPU, you can either ignore the warning, or just install the Kabylake driver from the same link given in Doug Smythies' answer. – Byte Commander Oct 15 '16 at 17:49