Re: Upcoming changes to Debian Linux kernel packages

On 25/09/2023 00.50, Bastian Blank wrote:
> Already built modules remain until someone deletes it.  So you can also
> switch back to the still installed older kernel version and it will have
> the still working module available.

This is what I expect not to work.

Assume I have Linux 6.6 and a third-party gpu driver module installed 
(so there are dkms and the Linux 6.6 headers as well) and everything is 
working fine.
Then I upgrade the system, which brings Linux 6.7 (along linux-image-6.6 
which is kept installed) and a new version of the gpu driver (which adds 
support for 6.7). So the old gpu module for 6.6 gets removed and a new 
one is built for 6.7 only (since there are only 6.7 headers now).
Unfortunately 6.7 breaks some exotic in-tree driver (which I desperately 
need), so I need to go back to 6.6. Oops, there is no gpu driver module 
any more. Recovery now needs manual intervention.

I'm not sure which class of bugs you are trying to solve with this 
proposed unversioned linux-headers change. IMO the current scheme of 
linux-headers-$version-$abi-$flavor matching 
linux-image-$version-$abi-$flavor works well. But perhaps something 
could be improved on the metapackage side. Ideally a user should install 
either meta-linux-image-without-headers-$flavor OR 
meta-linux-image-with-headers-$flavor (and ideally installing dkms 
should "automatically switch" to the with-headers variant, not sure how 
this could be done). The current scheme of having to install 
linux-image-$flavor AND linux-headers-$flavor is a bit tricky.
I'm open to implement improvements on the dkms side.

Andreas

PS: the proposed "more versioning in the linux-image packages" will 
solve some rare dkms issues where modules didn't get rebuilt after 
linux-headers-* was upgraded but $(uname -r) didn't change