The issue is not present in grub2-2.02~beta2-19 (latest version for 15.04 Vivid)
Using one machine with test kernels, update-grub outputs:
Found linux image: /boot/vmlinuz-3.17.0-custom
Found initrd image: /boot/initrd.img-3.17.0-custom
Found linux image: /boot/vmlinuz-3.17.0-rc1-custom
Found initrd image: /boot/initrd.img-3.17.0-rc1-custom
Found linux image: /boot/vmlinuz-3.16.0-29-generic
Found initrd image: /boot/initrd.img-3.16.0-29-generic
…
and grub2 lists 3.17.0-custom as the default kernel, not 3.17.0-rc1-custom.
Based on the changelog, this was probably fixed in grub2-2.00-20:
> * Backport from upstream:
> - Sort gnumach kernels in version order (closes: #725451).
> -- Colin Watson <email address hidden> 14 Nov 2013
I will mark this as Incomplete as suggested by the canned responses: "13.10 reached EOL on 17 July 2014…Please upgrade to the latest version and re-test."
The issue is not present in grub2-2.02~beta2-19 (latest version for 15.04 Vivid)
Using one machine with test kernels, update-grub outputs:
Found linux image: /boot/vmlinuz- 3.17.0- custom img-3.17. 0-custom 3.17.0- rc1-custom img-3.17. 0-rc1-custom 3.16.0- 29-generic img-3.16. 0-29-generic
Found initrd image: /boot/initrd.
Found linux image: /boot/vmlinuz-
Found initrd image: /boot/initrd.
Found linux image: /boot/vmlinuz-
Found initrd image: /boot/initrd.
…
and grub2 lists 3.17.0-custom as the default kernel, not 3.17.0-rc1-custom.
Based on the changelog, this was probably fixed in grub2-2.00-20:
> * Backport from upstream:
> - Sort gnumach kernels in version order (closes: #725451).
> -- Colin Watson <email address hidden> 14 Nov 2013
I will mark this as Incomplete as suggested by the canned responses: "13.10 reached EOL on 17 July 2014…Please upgrade to the latest version and re-test."