Comment 0 for bug 1579391

Tthe extlinux under Ubuntu has been broken since Vivid, and it is still not fixed in Ubuntu 16.04 LTS Xenial.

What I got:

In Vivid, having installed extlinux, I still don't have the extlinux.conf configuration file, so I do it manually again:

% extlinux --install /boot/extlinux
/boot/extlinux is device /dev/sda7

% dir -l /boot/extlinux
total 116
-r--r--r-- 1 root root 116632 May 1 21:21 ldlinux.c32

What is expected:

According to the official doc at http://www.syslinux.org/wiki/index.php/EXTLINUX, "extlinux --update /boot/extlinux" will
generate extlinux.conf under /boot/extlinux, and it has always been working like that before, until I'm testing it under Vivid.

In Xenial, things are still the same:

% apt-get install extlinux syslinux-common
Get:1 http://archive.ubuntu.com/ubuntu xenial/universe amd64 extlinux amd64 3:6.03+dfsg-11ubuntu1 [130 kB]
...
Get:5 http://archive.ubuntu.com/ubuntu xenial/main amd64 syslinux-common all 3:6.03+dfsg-11ubuntu1 [1,181 kB]
...
Preparing to unpack .../extlinux_3%3a6.03+dfsg-11ubuntu1_amd64.deb ...
Unpacking extlinux (3:6.03+dfsg-11ubuntu1) ...
Preparing to unpack .../syslinux-common_3%3a6.03+dfsg-11ubuntu1_all.deb ...
Unpacking syslinux-common (3:6.03+dfsg-11ubuntu1) ...
...
Setting up extlinux (3:6.03+dfsg-11ubuntu1) ...
Setting up syslinux-common (3:6.03+dfsg-11ubuntu1) ...
...

% ls -l /boot/vmlinuz* /boot/initrd* /boot/extlinux/*.conf /boot/extlinux/*.cfg
ls: cannot access '/boot/vmlinuz*': No such file or directory
ls: cannot access '/boot/extlinux/*.conf': No such file or directory
ls: cannot access '/boot/extlinux/*.cfg': No such file or directory
-rw-r--r-- 1 root root 37950863 May 7 14:58 /boot/initrd.img-4.4.0-21-generic

I had been able to workaround the problem by installing the working extlinux packages from prior to Vivid, but not any more under Xenial, in which I will get:

 extlinux --install /boot/extlinux
extlinux: cannot find device for path /boot/extlinux
extlinux: cannot open device (null)

I.e., using the previous working extlinux packages no longer works under Xenial. The system cannot boot any more.