Not sure if this was supposed to also be fixed in bionic-proposed yet,
but I assumed so and
it's not working there;  I'll test -proposed in artful and xenial next.

ubuntu@ubuntu:~$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=18.04
DISTRIB_CODENAME=bionic
DISTRIB_DESCRIPTION="Ubuntu Bionic Beaver (development branch)"
ubuntu@ubuntu:~$ uname -a
Linux ubuntu 4.15.0-13-generic #14-Ubuntu SMP Sat Mar 17 13:44:27 UTC
2018 x86_64 x86_64 x86_64 GNU/Linux

ubuntu@ubuntu:~$ apt-cache policy linux-image-virtual
linux-image-virtual:
  Installed: 4.15.0.13.14
  Candidate: 4.15.0.13.14
  Version table:
 *** 4.15.0.13.14 500
        500 http://archive.ubuntu.com/ubuntu bionic-proposed/main amd64 Packages
        100 /var/lib/dpkg/status
     4.15.0.12.13 500
        500 http://archive.ubuntu.com/ubuntu bionic/main amd64 Packages
ubuntu@ubuntu:~$ uname -a
Linux ubuntu 4.15.0-13-generic #14-Ubuntu SMP Sat Mar 17 13:44:27 UTC
2018 x86_64 x86_64 x86_64 GNU/Linux

ubuntu@ubuntu:~$ ls -al /dev/bcache*
brw-rw---- 1 root disk 251,   0 Mar 19 18:09 /dev/bcache0
brw-rw---- 1 root disk 251, 128 Mar 19 18:09 /dev/bcache1
brw-rw---- 1 root disk 251, 256 Mar 19 18:09 /dev/bcache2
brw-rw---- 1 root disk 251, 384 Mar 19 18:09 /dev/bcache3
ubuntu@ubuntu:~$ dmesg | grep bcache
[    1.005037] bcache: register_bdev() registered backing device sdb
[    1.011078] bcache: bch_journal_replay() journal replay done, 0
keys in 1 entries, seq 5
[    1.023834] bcache: bch_cached_dev_attach() Caching sdb as bcache0
on set 0dbdcc17-7af0-4318-bd57-bbdf5c7f1bfa
[    1.029237] bcache: register_cache() registered cache device sda
[    1.029555] bcache: register_bdev() registered backing device sdd
[    1.050543] bcache: bch_cached_dev_attach() Caching sdd as bcache1
on set 0dbdcc17-7af0-4318-bd57-bbdf5c7f1bfa
[    1.052124] bcache: register_bdev() registered backing device sde
[    1.054044] bcache: register_bdev() registered backing device sdf
[    1.058398] bcache: bch_journal_replay() journal replay done, 0
keys in 1 entries, seq 5
[    1.068618] bcache: bch_cached_dev_attach() Caching sdf as bcache3
on set d36b419d-a49d-42e2-95af-710138a20700
[    1.070652] bcache: bch_cached_dev_attach() Caching sde as bcache2
on set d36b419d-a49d-42e2-95af-710138a20700
[    1.076326] bcache: register_cache() registered cache device sdc
[    4.090280] bcache: register_bcache() error /dev/sdc: device
already registered
[    4.091070] bcache: register_bcache() error /dev/sdd: device
already registered
[    4.094397] bcache: register_bcache() error /dev/sde: device
already registered
[    4.095253] bcache: register_bcache() error /dev/sda: device
already registered
[    4.103178] bcache: register_bcache() error /dev/sdb: device
already registered
[    4.115378] bcache: register_bcache() error /dev/sdf: device
already registered

On Mon, Mar 19, 2018 at 5:56 AM, Stefan Bader
<email address hidden> wrote:
> This bug is awaiting verification that the kernel in -proposed solves
> the problem. Please test the kernel and update this bug with the
> results. If the problem is solved, change the tag 'verification-needed-
> artful' to 'verification-done-artful'. If the problem still exists,
> change the tag 'verification-needed-artful' to 'verification-failed-
> artful'.
>
> If verification is not done by 5 working days from today, this fix will
> be dropped from the source code, and this bug will be closed.
>
> See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how
> to enable and use -proposed. Thank you!
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1729145
>
> Title:
>   /dev/bcache/by-uuid links not created after reboot
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1729145/+subscriptions