My previously completely stable Mageia 3 desktop system failed to boot properly yesterday. Immediately after systemd kicks in, there's an error,

Failed to insert module 'autofs4'

followed later by (presumably consequential) error messages

Failed to open /dev/autofs: No such file or directory
Failed to initialize automounter: No such file or directory
Failed to set up automount Arbitrary Executable File Formats File

and later yet some more stuff on mount failures - looks like the first linux ext4 partitions (including /) mount okay, but nothing thereafter (and that breaks the boot, but leaves me able to do a "maintenance" login).

lsmod shows only a dozen basic modules are loaded. So my suspicion is that the underlying problem is that the modules aren't loading properly. (To eliminate one other "gotcha": none of the partitions are anything like full.)

Since I hadn't changed anything on the system (as far as i can remember!) I first suspected some hardware problem. This suspicion was encouraged by a fresh install, after which I got exactly the same problem.

But badblock -v isn't showing any problems, and the system boots into Windows(7) uncomplainingly. [There are two HDDs, one for backup, both split ca. 50:50 between Windows(7) and linux partitions.]

So i'm feeling stumped at what to try next...any ideas? Mr Google is only turning up bug reports, and i couldn't see anything useful previously posted on this forum (but that could be user error...)

I have had a similar problem with systemd and I solved it recompiling the kernel.
I use debian and after upgrade from wheezy to jessie/sid sysvinit was changed by systemd, for this reason my computer stopped booting. When I booted my computer on recovery mode and open the file /var/log/dmesg I could see the same error you have said.

Try to recompile your kernel and modify your .config file, in that file you must change the option CONFIG_AUTOFS4_FS=m to CONFIG_AUTOFS4_FS=y, and then compile the new kernel.

I hope you can solve your problem.

One possibility is that you've requested that a filesystem driver be stored ... uhh ... in a file. There could definitely be problems with that . . .

As suggested above, be sure that all filesystem drivers are specified to be compiled into the kernel. Include only the ones you know that you'll need. (Filesystems for external or USB devices can be modules.) Then, recompile the entire kernel including all modules, to make sure that everything is compiled and therefore current with everything else. (Linux will detect and will not load a module that's incompatible with itself.)