Comment 29 for bug 1874453

Both problems persist on 20200522.0.0, here is the kernel panic and reboot:

[ 0.883971] VFS: Cannot open root device "PARTUUID=43931bda-01" or unknown-block(0,0): error -6
[ 0.885744] Please append a correct "root=" boot option; here are the available partitions:
[ 0.887371] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
[ 0.888956] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.4.0-31-generic #35-Ubuntu
[ 0.890427] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 0.891863] Call Trace:
[ 0.892322] dump_stack+0x6d/0x9a
[ 0.892865] panic+0x101/0x2e3
[ 0.893466] mount_block_root+0x23f/0x2e8
[ 0.894322] mount_root+0x38/0x3a
[ 0.894984] prepare_namespace+0x13f/0x194
[ 0.895776] kernel_init_freeable+0x231/0x255
[ 0.896743] ? rest_init+0xb0/0xb0
[ 0.897499] kernel_init+0xe/0x100
[ 0.898283] ret_from_fork+0x35/0x40
[ 0.899058] Kernel Offset: 0x32400000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[ 0.900974] ACPI MEMORY or I/O RESET_REG.
[ 0.000000] Linux version 5.4.0-31-generic (buildd@lgw01-amd64-059) (gcc version 9.3.0 (Ubuntu 9.3.0-10ubuntu2)) #35-Ubuntu SMP Thu May 7 20:20:34 UTC 2020 (Ubuntu 5.4.0-31.35-generic 5.4.34)