I cannot reproduce with your instruction.

# dkms status
tp_smapi-dkms, 0.42, 4.18.16-arch1-1-ARCH, x86_64: installed
tp_smapi-dkms, 0.42, 4.18.3-seblu, x86_64: installed
tp_smapi-dkms, 0.42, 4.19.0-seblu, x86_64: installed
tp_smapi-dkms, 0.42, 4.9.128-seblu, x86_64: installed

The log of the installation:

# dkms install tp_smapi-dkms/0.42 -k 4.18.16-arch1-1-ARCH

Kernel preparation unnecessary for this kernel. Skipping...

Building module:
cleaning build area...
make -j8 KERNELRELEASE=4.18.16-arch1-1-ARCH KVER=4.18.16-arch1-1-ARCH HDAPS=1...
cleaning build area...
Kernel cleanup unnecessary for this kernel. Skipping...

DKMS: build completed.

hdaps.ko:
Running module version sanity check.
- Original module
- No original module exists within this kernel
- Installation
- Installing to /usr/lib/modules/4.18.16-arch1-1-ARCH/updates/

thinkpad_ec.ko:
Running module version sanity check.
- Original module
- No original module exists within this kernel
- Installation
- Installing to /usr/lib/modules/4.18.16-arch1-1-ARCH/extra/

tp_smapi.ko:
Running module version sanity check.
- Original module
- No original module exists within this kernel
- Installation
- Installing to /usr/lib/modules/4.18.16-arch1-1-ARCH/extra/

depmod....

DKMS: install completed.


So far, original_module happen when the built modules is already in extra or updates directories. Kernel provided modules doesn't belong in these directory. So how you hdsa modules did find its way in these directories?

I guess you are working on 2.6.x branch, which is broken even with your last patch merged upstream.

Hmmm, very interesting... You are right. "original_module exists" message should not happen in my case.
Yes, I'm on 2.6.x... well, no, actually it's master.
WTF. I have to check this again.
Thanks.

I had a look at this again. "original_module" should happen indeed if a module replaces a kernel module.

I realized there is another upstream patch needed, additionally to my hook patch here.
My hook patch fixes the problem of not uninstalling dkms modules on a kernel update because of not matching "installed (original_module exists)".

With my patch:
[c0d3@z3r0 tmp]$ dkms status
chipsec-dkms, git: added
thinkpad-wmi, r12.aa470c9, 4.19.0-rc8-r1540570303-g18d0eae30-1-c0, x86_64: installed
tp_smapi-dkms, 0.42, 4.19.0-rc8-r1540570303-g18d0eae30-1-c0, x86_64: installed (original_module exists)
vboxhost, 5.2.18_OSE: added

Without my patch:
[c0d3@z3r0 tmp]$ dkms status
chipsec-dkms, git: added
thinkpad-wmi, r12.aa470c9, 4.19.0-rc8-r1540570303-g18d0eae30-1-c0, x86_64: installed
tp_smapi-dkms, 0.42, 4.19.0-rc8-r1540570303-g18d0eae30-1-c0, x86_64: installed (original_module exists)
tp_smapi-dkms, 0.42, 4.19.0-rc6-r1538316935-g17b57b188-1-c0, x86_64: installed (original_module exists)
vboxhost, 5.2.18_OSE: added

Without my hook patch, the rc6 kernel module does not get removed.




DKMS does not move the original module back to it's original place but into /updates.
That is why it is not removed by pacman! That's the patch needed upstream; move original_module back to it's original location.


[c0d3@z3r0 linux-c0]$ sudo dkms install tp_smapi-dkms/0.42 -k 4.19.0-rc8-r1540570303-g18d0eae30-1-c0

Creating symlink /var/lib/dkms/tp_smapi-dkms/0.42/source ->
/usr/src/tp_smapi-dkms-0.42

DKMS: add completed.

[...]

DKMS: build completed.

hdaps.ko:
Running module version sanity check.
- Original module
- Found /usr/lib/modules/4.19.0-rc8-r1540570303-g18d0eae30-1-c0/kernel/drivers/platform/x86/hdaps.ko
- Storing in /var/lib/dkms/tp_smapi-dkms/original_module/4.19.0-rc8-r1540570303-g18d0eae30-1-c0/x86_64/
- Archiving for uninstallation purposes
- Installation
- Installing to /usr/lib/modules/4.19.0-rc8-r1540570303-g18d0eae30-1-c0/updates/

[...]

depmod...

DKMS: install completed.


[c0d3@z3r0 linux-c0]$ sudo dkms uninstall tp_smapi-dkms/0.42 -k 4.19.0-rc8-r1540570303-g18d0eae30-1-c0
[sudo] password for root:

-------- Uninstall Beginning --------
Module: tp_smapi-dkms
Version: 0.42
Kernel: 4.19.0-rc8-r1540570303-g18d0eae30-1-c0 (x86_64)
-------------------------------------

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

hdaps.ko:
- Uninstallation
- Deleting from: /usr/lib/modules/4.19.0-rc8-r1540570303-g18d0eae30-1-c0/updates/
- Original module
- Archived original module found in the DKMS tree
- Moving it to: /usr/lib/modules/4.19.0-rc8-r1540570303-g18d0eae30-1-c0/updates/

[...]

depmod...

Removing original_module from DKMS tree for kernel 4.19.0-rc8-r1540570303-g18d0eae30-1-c0 (x86_64)

DKMS: uninstall completed.

Upstream issue opened: https://github.com/dell/dkms/issues/64
The patch here is still needed to keep dkms status clean!
EDIT: If upstream does not touch original kernel modules, this patch ist NOT needed, since "original_module exists" will not be shown.

UPDATE: All problems seem to be solved, when I comment out this line:
#((module_count == 1)) && archive_pref4=${installed_modules[0]}

UPDATE: PR at upstream: https://github.com/dell/dkms/pull/65
The patch here can be dropped then.

PR at upstream got merged. This is resolved now