On Sun, Jul 10, 2022 at 03:02:52PM +0200, Alexander Grund wrote: > On 10.07.22 14:48, Greg KH wrote: > >>> What 4.4.y Android devices are still supported by their vendors? And > >>> are they still getting kernel updates? > >> > >> Actually the issue is that those devices are not supported by their vendors anymore, so they may only get updates through LineageOS. > >> That is a third-party Android build where maintainers rely on proprietary binaries from the original phone which are tied to a specific kernel. > >> Hence when the device falls out of support having a 4.4 kernel in the last release there is no way for those maintainers to switch to a newer kernel. > >> That's the situation e.g. I am in right now: Providing (mostly) security updates for a good phone that fell out of vendor support > >> by using LineageOS for an updated Android system and e.g. the CIP maintained SLTS 4.4 kernel. > >> And I know of at least 2 other devices using the same kernel as they share the platform. > > > > All of those devices that wish to keep working should just forward port > > their tree to newer kernel versions so that they can stay secure and > > working properly. It is far easier to do that than to attempt to keep > > older kernel trees alive over time. I've done both in the past and it's > > always simpler to move forward. > > > > So why not just do that instead of attempting to keep these old kernels > > alive? Do the effort once and then you can rely on the community's > > help. Otherwise you are stuck on your own for forever. > > Because forward porting is not possible. > As mentioned the original device vendor does no longer support those devices > so what the community has is a blob of binaries compiled against a specific > kernel version with no access to their sources. That's a lovely GPL violation that I am sure those vendors would be glad to fix up and provide the source for. Especially if those vendors are wanting to use newer kernel versions in newer devices :) > As those binaries (mostly hardware "drivers") are required to use the device, > recompilation isn't possible and they are likely coupled to the kernel version > specific API/ABI "we" (me and maintainers of similar devices) have to stick to that kernel. If you do not know what sources those blobs are built from, then trying to keep a stable abi is very very difficult, as I know from experience. Good luck! greg k-h
