Because if in a few years I have a device whose driver is written in Rust, a new kernel version might have simply dropped or broken my device driver, and I cannot use my device anymore. But sure, if R4L wants to stay a second-class citizen forever, it can still be acceptable.

this isn't policy forever. it's policy for now. if r4l succeeds, the policy will change.

> Because if in a few years I have a device whose driver is written in Rust, a new kernel version might have simply dropped or broken my device driver, and I cannot use my device anymore.

At least for Debian, all you need to do if you hit such a case is to simply go and choose the old kernel in the Grub screen. You don't even need to deal with installing an older package and dealing with version conflicts or other pains of downgrading.

I hope you're not seriously suggesting this as a reasonable workflow.

For my server or laptop at home, sure. Why not. For servers in commercial fleets you should have staged rollouts as a policy anyway so if you do it right you shouldn't get hit.

Distros should be your firewall against that sort of thing. Just don't use a distro with a non-existent kernel upgrade process.

It is only a problem if you compile the kernel directly from the source tree instead of using the packages provided by your Linux distribution.