linuxPackages: point to latests longterm kernel 3.18

[domenkozar]

http://www.linux.com/news/software/linux-kernel/815939-linux-kernel-3189-is-now-an-lts-long-term-support-release

[vcunat]

+1, unless there are lasting btrfs problems with it, as suggested in d9ce51d :-)

Hmm, to be maintained by Sasha Levin.

[thoughtpolice]

lgtm

[domenkozar]

Going to merge this as soon as master channel updates after a month.

[wkennington]

How is this going to work with grsecurity? will the stable versions just diverge for the vanilla vs grsec kernels?

[vcunat]

I don't really know anything about grsecurity, but it doesn't seem they support 3.18 (anymore): https://grsecurity.net/download.php.

[thoughtpolice]

@wkennington Yes, that's correct. There's really not much we can do about this, as there doesn't exist any archive of old patches[1]. There are two grsec branches: 'unstable', which tracks the latest 'mainline' Linux release (for the most part), and 'stable', which tracks specific, older kernels marked 'stable' by the developers, like 3.2, or 3.14. Not every Linux -stable release has a grsec release. These are the options we have, meaning the kernel version necessarily deviates if we want linuxPackages to always track the latest stable (3.18, in this case). The alternative is that linuxPackages is always synced to the most recent grsec stable release, which in this case would be 3.14.

So divergence here isn't really an issue, I'd say. Also, it's not clear to me what the grsec release schedule is like anyway - the next stable grsec kernel may be 4.0, or 4.2, or whatever we choose to ship in 15.10, or not. So we'll have to figure this out down the road, I think...

[1] Actually, there might be a mirror maintained by the Hardened Gentoo people, but I can't remember where their sources are... Alternatively, I've been meaning to setup a grsec patches -> git mirror for a while.

[joachifm]

@thoughtpolice I've recently rolled a custom linux 3.18 config with grsecurity pulled from hardened gentoo's repository.
Works very well for me thus far.

[domenkozar]

@vcunat unfortunately the bug is a real problem: "Current stable kernels (< 3.19.4) may fail to mount btrfs and deadlock on boot" -> https://btrfs.wiki.kernel.org/index.php/Gotchas

[domenkozar]

So let's wait for another minor bump of kernels and then merge.

[vcunat]

It seems to me that both latest 3.14.37 and 3.18.11 are also affected by that problem.

[abbradar]

Ouch, I've run into this problem several times from Monday! For those affected I recommend using boot.debug1devices and running btrfs check, I was forced to make and boot a LiveUSB to fix this until I found out the other way. Can we perhaps apply https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=9c4f61f01d269815bb7c37be3ede59c5587747c6 to the latest kernel while point release is on way?

[abbradar]

I've made a PR 1 with the patch.