> Paul Tobias <tobias.pal <at> gmail.com> writes: > > It works, but a patched kernel is needed. Take a look at > > https://forums.gentoo.org/viewtopic-p-7275724.html The patch there was > > still working on the latest kernel a while ago.
The patch from the forum thread does indeed work, and just reading it makes it clear *why* it doesn't work in linus' kernel. Thanks! > > I used it on 2 of my systems, but I moved on and now using dracut > > everywhere. While I agree that dracut (/genkernel) is painless, not hard to setup and *should* be the preferred way to boot nowadays, I felt that its a matter of principle that this should work without one. I mean, they even mention in the btrfs wiki that this works (supposedly). In any case I feel like this is a bug in the kernel. Once I work up the courage I'll contact the btrfs(/kernel) mailing list and see what they have to say about this. On Mon, 10 Aug 2015, James wrote: > I not sure but the OpenSuse btrfs (non-raid1) standard install uses only > btrfs partition types, including /boot and all other partitions. I do not > think it uses dracut or others, but I'm not that use to opensuse to make > install. I happen to have a fairly recent OpenSuse vm lying around, featuring a pure btrfs set-up - boot in a subvolume etc. It's non-raid1 but OpenSuse uses dracut so they do not have the problem that I brought up anyway. In general I have not had any problems setting up similar gentoo systems running pure btrfs in raid1/single mode. Those systems, however, all have initramfs' - not that that's a bad thing but see above. Btw. testing the mentioned patch turned out to be a 5 minute thing. qemu-img create to make 2 disk images, qemu boot sysresuecd, create 2 device btrfs volume, mount, unpack stage3 and shutdown. Patch spare kernel in host, compile and boot passing the kernel and cmdline from outside the guest. Works nicely for quick testing (forgot to set root passwd? who cares, it boots!).
