The bug came back today with 16.04 (fully updated just yesterday). Kernel always failed with the "unable to mount root" BT on multiple could boot attempts.
Again, I needed to boot with a livecd in order to be able to boot my machine again. I only runned btrfs check with no "--repair" and not error was shown. I mounted it, unmounted and rebooted. After that, system booted normally. It seems that btrfs "recovery itself" on boot, with the simple "btrfs check" or with the mount.
It seems that btrfs is able to recover but maybe the kernel could not find the FS. My system defines root in kernel cmdline as root=UUID=9051c9b6-070c-443a-8f8f-f7c23c1b01c6. Maybe a dirty btrfs can mess with kernel procedure to list FS by UUID?
The bug came back today with 16.04 (fully updated just yesterday). Kernel always failed with the "unable to mount root" BT on multiple could boot attempts.
Again, I needed to boot with a livecd in order to be able to boot my machine again. I only runned btrfs check with no "--repair" and not error was shown. I mounted it, unmounted and rebooted. After that, system booted normally. It seems that btrfs "recovery itself" on boot, with the simple "btrfs check" or with the mount.
It seems that btrfs is able to recover but maybe the kernel could not find the FS. My system defines root in kernel cmdline as root=UUID= 9051c9b6- 070c-443a- 8f8f-f7c23c1b01 c6. Maybe a dirty btrfs can mess with kernel procedure to list FS by UUID?