内核没更新成功是什么情况？

$ ls -l /
lrwxrwxrwx 1 root root 31 Oct 27 17:59 vmlinuz -> boot/vmlinuz-3.16-0.bpo.2-amd64
lrwxrwxrwx 1 root root 26 Dec 31 2013 vmlinuz.old -> boot/vmlinuz-3.2.0-4-amd64

aaron@aaronwang:/var/www/xidi$ uname -v
#1 SMP Debian 3.2.51-1

root@aaronwang:~# apt-get -t wheezy-backports install linux-image-amd64
Reading package lists... Done
Building dependency tree
Reading state information... Done
linux-image-amd64 is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 43 not upgraded