some SM15K systems fail to boot after deployment - drop into initramfs shell

Some SM15K fail to boot after told to localboot.

Related bugs:
 * bug 1463046: installation of multipath-tools-boot can break boot
 * bug 1462530: multipath errors on vivid and wily kernel?

PXE Request - local boot Sat, 06 Jun. 2015 02:42:40
Installation complete - Node disabled netboot Sat, 06 Jun. 2015 02:42:06
PXE Request - curtin install Sat, 06 Jun. 2015 02:37:01

After installation and the nodes trying to localboot, I see the following error when trying to load the OS:

   37.506366] e1000 0000:08:00.1 eth7: Intel(R) PRO/1000 Network Connection
Begin: Loading essential drivers[ 38.721471] random: nonblocking pool is initialized
 ... done.
Begin: Running /scripts/init-premount ... done.
Begin: Mounting r[ 38.871904] hidraw: raw HID events driver (C) Jiri Kosina
oot file system [ 38.942606] usbcore: registered new interface driver usbhid
[ 39.023798] usbhid: USB HID core driver
... Begin: Running /scripts/local-top ... Begin: Loading multipath modules ... Success: loaded module dm-multipath.
Failure: failed to load module dm-emc.
done.
Begin: Waiting for scsi storage ... done.
Begin: Discovering multipaths ... done.
done.
Begin: Running /scripts/local-premount ... done.
mount: mounting /dev/disk/by-uuid/feaa393b-1aeb-4a0d-bd00-76b7dd8bc99b on /root failed: Device or resource busy
Begin: Running /scripts/local-bottom ... done.
done.
Begin: Running /scripts/init-bottom ... mount: mounting /dev on /root/dev failed: No such file or directory
done.
mount: mounting /sys on /root/sys failed: No such file or directory
mount: mounting /proc on /root/proc failed: No such file or directory
Target filesystem doesn't have requested /sbin/init.
No init found. Try passing init= bootarg.

The installation log shows:

invoke-rc.d: policy-rc.d denied execution of start.
update-rc.d: warning: start and stop actions are no longer supported; falling back to defaults
Processing triggers for ureadahead (0.100.0-16) ...
Setting up multipath-tools-boot (0.4.9-3ubuntu10) ...
update-initramfs: deferring update (trigger activated)
Processing triggers for libc-bin (2.19-10ubuntu2.3) ...
Processing triggers for initramfs-tools (0.103ubuntu8) ...
update-initramfs: Generating /boot/initrd.img-3.16.0-31-generic
df: Warning: cannot read table of mounted file systems
update-initramfs: Generating /boot/initrd.img-3.16.0-31-generic
df: Warning: cannot read table of mounted file systems
Replacing config file /etc/default/grub with new version
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-3.16.0-31-generic
Found initrd image: /boot/initrd.img-3.16.0-31-generic
done
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-3.16.0-31-generic
Found initrd image: /boot/initrd.img-3.16.0-31-generic
done
Installing for i386-pc platform.
Installation finished. No error reported.

This is with:
ii maas 1.8.0~rc3+bzr3997-0ubuntu1~trusty1 all

and

ii curtin-common 0.1.0~bzr213-0ubuntu1~ppa0 all Library and tools for curtin installer
ii python-curtin 0.1.0~bzr213-0ubuntu1~ppa0 all Library and tools for curtin installer

Following workaround was applied to trusty and precise preseeds:

$ tail -n 3 /etc/maas/preseeds/curtin_userdata
multipath:
   mode: disabled

and system deployed ok.