问为什么会出现dkms状态“警告！安装模块之间的差异”？

EN

generic@motorbrot:~$ sudo dkms status
zfs, 0.8.4, 5.3.0-51-generic, x86_64: installed (WARNING! Diff between built and installed module!) (WARNING! Diff between built and installed module!) (WARNING! Diff between built and installed module!) (WARNING! Diff between built and installed module!) (WARNING! Diff between built and installed module!) (WARNING! Diff between built and installed module!) (WARNING! Diff between built and installed module!) (WARNING! Diff between built and installed module!)
zfs, 0.8.4, 5.3.0-53-generic, x86_64: installed (WARNING! Diff between built and installed module!) (WARNING! Diff between built and installed module!)

generic@motorbrot:~$ sudo dkms remove -m zfs -v 0.8.4 -k 5.3.0-53-generic

-------- Uninstall Beginning --------
Module:  zfs
Version: 0.8.4
Kernel:  5.3.0-53-generic (x86_64)
-------------------------------------

Status: Before uninstall, this module version was ACTIVE on this kernel.

zavl.ko:
 - Uninstallation
   - Deleting from: /lib/modules/5.3.0-53-generic/
rmdir: failed to remove '': No such file or directory
 - Original module
   - No original module was found for this module on this kernel.
   - Use the dkms install command to reinstall any previous module version.

# [skipping long output that all looks similar but for different something.ko]

spl.ko:
 - Uninstallation
   - Deleting from: /lib/modules/5.3.0-53-generic/updates/dkms/
 - Original module
   - No original module was found for this module on this kernel.
   - Use the dkms install command to reinstall any previous module version.

depmod...

DKMS: uninstall completed.
generic@motorbrot:~$ sudo dkms install -m zfs -v 0.8.4 -k 5.3.0-53-generic

Kernel preparation unnecessary for this kernel.  Skipping...

Running the pre_build script:

# [Skipping "checking for blah... blah" outputs]

Building module:
cleaning build area...
make -j8 KERNELRELEASE=5.3.0-53-generic............

Running the post_build script:
Signing module:
 - /var/lib/dkms/zfs/0.8.4/5.3.0-53-generic/x86_64/module/spl.ko
 - /var/lib/dkms/zfs/0.8.4/5.3.0-53-generic/x86_64/module/icp.ko
 - /var/lib/dkms/zfs/0.8.4/5.3.0-53-generic/x86_64/module/zfs.ko
 - /var/lib/dkms/zfs/0.8.4/5.3.0-53-generic/x86_64/module/zcommon.ko
 - /var/lib/dkms/zfs/0.8.4/5.3.0-53-generic/x86_64/module/zlua.ko
 - /var/lib/dkms/zfs/0.8.4/5.3.0-53-generic/x86_64/module/znvpair.ko
 - /var/lib/dkms/zfs/0.8.4/5.3.0-53-generic/x86_64/module/zunicode.ko
 - /var/lib/dkms/zfs/0.8.4/5.3.0-53-generic/x86_64/module/zavl.ko
Secure Boot not enabled on this system.
cleaning build area...

DKMS: build completed.

zavl.ko:
Running module version sanity check.

Good news! Module version 0.8.4-1 for zavl.ko
exactly matches what is already found in kernel 5.3.0-53-generic.
DKMS will not replace this module.
You may override by specifying --force.

znvpair.ko:
Running module version sanity check.
 - Original module
 - Installation
   - Installing to /lib/modules/5.3.0-53-generic/updates/dkms/

zunicode.ko:
Running module version sanity check.

Good news! Module version 0.8.4-1 for zunicode.ko
exactly matches what is already found in kernel 5.3.0-53-generic.
DKMS will not replace this module.
You may override by specifying --force.

zcommon.ko:
Running module version sanity check.
 - Original module
 - Installation
   - Installing to /lib/modules/5.3.0-53-generic/updates/dkms/

zfs.ko:
Running module version sanity check.
 - Original module
 - Installation
   - Installing to /lib/modules/5.3.0-53-generic/updates/dkms/

icp.ko:
Running module version sanity check.
 - Original module
 - Installation
   - Installing to /lib/modules/5.3.0-53-generic/updates/dkms/

zlua.ko:
Running module version sanity check.
 - Original module
 - Installation
   - Installing to /lib/modules/5.3.0-53-generic/updates/dkms/

spl.ko:
Running module version sanity check.
 - Original module
 - Installation
   - Installing to /lib/modules/5.3.0-53-generic/updates/dkms/

depmod...

DKMS: install completed.