Bug#707831: UUID detection code broken, wrongly uses UUID

[Daniel Pocock]

Package: grub-pc
Version: 1.99-27+deb7u1
Severity: serious



/etc/grub.d/10_linux wrongly adds root=UUID entries to grub.cfg if
grub-probe fails

Specifically, in one case I observed grub-probe had failed because a new
disk was added (some months ago) and grub-mkdevicemap had not been run.
 Users typically see this error in that case:


/usr/sbin/grub-probe: error: Couldn't find PV pv1. Check your device.map.


The update-grub script should refuse to write out grub.cfg after such
failures.  Currently it appears to default to UUID= entries, and if root
is on LVM, the system is then unbootable.