Comment 14 for bug 1068299

If amd64-microcode is already installed linux-firmware 1.100 can't be installed:

sworddragon@ubuntu:~$ sudo apt-get dist-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
The following packages will be upgraded:
  linux-firmware
1 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B/21.1 MB of archives.
After this operation, 815 kB of additional disk space will be used.
Do you want to continue [Y/n]?
debconf: delaying package configuration, since apt-utils is not installed
(Reading database ... 90931 files and directories currently installed.)
Preparing to replace linux-firmware 1.99 (using .../linux-firmware_1.100_all.deb) ...
Unpacking replacement linux-firmware ...
dpkg: error processing /var/cache/apt/archives/linux-firmware_1.100_all.deb (--unpack):
 trying to overwrite '/lib/firmware/amd-ucode/microcode_amd_fam15h.bin', which is also in package amd64-microcode 1.20120910-2
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
Errors were encountered while processing:
 /var/cache/apt/archives/linux-firmware_1.100_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

Maybe linux-firmware should remove amd64-microcode if it is already completely included.