Comment 39 for bug 1761796

Tested the 4.17 kernel, and this is the issue I now see:

[...]
[ 17.340040] raid6: sse2x1 xor() 2828 MB/s
[ 17.408036] raid6: sse2x2 gen() 7445 MB/s
[ 17.472037] raid6: sse2x2 xor() 5425 MB/s
[ 17.540032] raid6: sse2x4 gen() 10259 MB/s
[ 17.604037] raid6: sse2x4 xor() 6286 MB/s
[ 17.668034] raid6: avx2x1 gen() 14089 MB/s
[ 17.732034] raid6: avx2x1 xor() 9346 MB/s
[ 17.796035] raid6: avx2x2 gen() 16758 MB/s
[ 17.860033] raid6: avx2x2 xor() 9779 MB/s
[ 17.924034] raid6: avx2x4 gen() 19079 MB/s
[ 17.988036] raid6: avx2x4 xor() 11383 MB/s
[ 18.007313] raid6: using algorithm avx2x4 gen() 19079 MB/s
[ 18.031519] raid6: .... xor() 11383 MB/s, rmw enabled
[ 18.054148] raid6: using avx2x2 recovery algorithm
[ 18.076927] xor: automatically using best checksumming function avx
[ 18.109754] async_tx: api initialized (async)
done.
Begin: Running /scripts/init-premount ... done.
Begin: Mounting root file system ... Begin: Running /scripts/local-top ... done.
Begin: Running /scripts/local-premount ... [ 18.199553] Btrfs loaded, crc32c=crc32c-intel
Scanning for Btrfs filesystems
done.
Begin: Waiting for root file system ... Begin: Running /scripts/local-block ... mdadm: No devices listed in conf file were found.
done.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: error opening /dev/md?*: No such file or directory
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
mdadm: No devices listed in conf file were found.
done.
Gave up waiting for root file system device. Common problems:
 - Boot args (cat /proc/cmdline)
   - Check rootdelay= (did the system wait long enough?)
 - Missing modules (cat /proc/modules; ls /dev)
ALERT! UUID=bd0dbca3-60b8-474e-ac82-96f1b9ff9cc2 does not exist. Dropping to a shell!

BusyBox v1.27.2 (Ubuntu 1:1.27.2-2ubuntu3) built-in shell (ash)
Enter 'help' for a list of built-in commands.