I have a Toshiba Laptop x86_64 running OpenSuSE6.2. A short time ago
I noticed that when I boot it no longer goes into grub2 with a menu
but flashes up a message about a file or possibly a missing file (much
too fast to read but maybe “sparse file not permitted”) and then it boots into
kernel 3.16.7-21-desktop
Looking at the /boot directory I see files for this kernel and a newer
3.16.7-24-desktop. Naturally nothing seems to be logged.
It would be good to use updated kernels! I have no understanding of
grub2 but used to be able to fiddle grub. Possibly relevant is that
the filing system is btrfs which I know confuses hibernation.
If a menu entry to be booted is set in there, the menu isn’t displayed any more.
And as grub2 cannot write to btrfs partitions, it cannot reset that by itself.
That problem is not directly related to hibernation at all.
It happens whenever you (or something) sets an entry to be booted.
Hibernation does this to prevent you from booting another OS and mounting your partitions there, as this would cause data loss/filesystem corruption.
But also KDE’s “Restart” menu does this, or you can manually via “grub2-once” or “grub2-reboot”.
As mentioned, the actual problem is that grub2 cannot revert that setting after booting the entry, because it cannot write to btrfs filesystems.
This has been “fixed” already in Tumbleweed and SLE12 btw, grub2 uses a special area in btrfs for saving the so-called “environment block” (i.e. what grubenv contains) instead of a standard file.
I hope we can get an updated grub2 as update for 13.2 as well…