当我尝试删除一些旧包时出现错误：
per@pyraohms:~$ sudo apt-get autoremove
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
linux-image-extra-4.13.0-16-generic
0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
6 not fully installed or removed.
After this operation, 163 MB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 346761 files and directories currently installed.)
Removing linux-image-extra-4.13.0-16-generic (4.13.0-16.19) ...
depmod: FATAL: could not load /boot/System.map-4.13.0-16-generic: No such file or directory
run-parts: executing /etc/kernel/postinst.d/apt-auto-removal 4.13.0-16-generic /boot/vmlinuz-4.13.0-16-generic
run-parts: executing /etc/kernel/postinst.d/initramfs-tools 4.13.0-16-generic /boot/vmlinuz-4.13.0-16-generic
update-initramfs: Generating /boot/initrd.img-4.13.0-16-generic
WARNING: missing /lib/modules/4.13.0-16-generic
Ensure all necessary drivers are built into the linux image!
depmod: ERROR: could not open directory /lib/modules/4.13.0-16-generic: No such file or directory
depmod: FATAL: could not search modules: No such file or directory
W: plymouth module (/usr/lib/x86_64-linux-gnu/plymouth//.so) missing, skipping that theme.
depmod: WARNING: could not open /var/tmp/mkinitramfs_V8ELWC/lib/modules/4.13.0-16-generic/modules.order: No such file or directory
depmod: WARNING: could not open /var/tmp/mkinitramfs_V8ELWC/lib/modules/4.13.0-16-generic/modules.builtin: No such file or directory
/usr/sbin/update-initramfs: 174: /usr/sbin/update-initramfs: sync: not found
run-parts: /etc/kernel/postinst.d/initramfs-tools exited with return code 127
dpkg: error processing package linux-image-extra-4.13.0-16-generic (--remove):
subprocess installed post-removal script returned error exit status 1
Errors were encountered while processing:
linux-image-extra-4.13.0-16-generic
E: Sub-process /usr/bin/dpkg returned an error code (1)
有谁知道这里出了什么问题？