我正在尝试卸载一些内核版本以释放空间/boot。我确实kernelver=$(uname -r | sed -r 's/-[a-z]+//'); dpkg -l linux-{image,headers}-"[0-9]*" | awk '/ii/{print $2}'找到了安装了哪些内核版本，但
linux-headers-3.13.0-87
linux-headers-3.13.0-87-generic
linux-headers-3.13.0-91
linux-headers-3.13.0-91-generic
linux-headers-3.13.0-92
linux-headers-3.13.0-92-generic
linux-headers-4.2.0-27
linux-headers-4.2.0-27-generic
linux-headers-4.2.0-34
linux-headers-4.2.0-34-generic
linux-headers-4.2.0-36
linux-headers-4.2.0-36-generic
linux-headers-4.2.0-41
linux-headers-4.2.0-41-generic
linux-headers-4.2.0-42
linux-headers-4.2.0-42-generic
linux-image-4.2.0-36-generic
linux-image-4.2.0-41-generic
linux-image-4.2.0-42-generic
然后我照做了ls /boot，得到了：
abi-4.2.0-35-generic lost+found
abi-4.2.0-36-generic memtest86+.bin
abi-4.2.0-41-generic memtest86+.elf
abi-4.2.0-42-generic memtest86+_multiboot.bin
config-4.2.0-35-generic System.map-4.2.0-35-generic
config-4.2.0-36-generic System.map-4.2.0-36-generic
config-4.2.0-41-generic System.map-4.2.0-41-generic
config-4.2.0-42-generic System.map-4.2.0-42-generic
efi vmlinuz-4.2.0-35-generic
grub vmlinuz-4.2.0-35-generic.efi.signed
initrd.img-4.2.0-35-generic vmlinuz-4.2.0-36-generic
initrd.img-4.2.0-35-generic.old-dkms vmlinuz-4.2.0-36-generic.efi.signed
initrd.img-4.2.0-36-generic vmlinuz-4.2.0-41-generic
initrd.img-4.2.0-41-generic vmlinuz-4.2.0-41-generic.efi.signed
initrd.img-4.2.0-41-generic.old-dkms vmlinuz-4.2.0-42-generic
initrd.img-4.2.0-42-generic vmlinuz-4.2.0-42-generic.efi.signed
initrd.img-4.2.0-42-generic.old-dkms
这里发生了什么？