Comment 28 for bug 1925008

installed mentioned kernel version an did a memory hot-plugging test which was sucessfull

kernel version:
root@ubuntu:/boot# uname -a
Linux ubuntu 5.4.0-1040-kvm #41-Ubuntu SMP Fri May 14 20:43:17 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

module in kernel configuration is set:
root@ubuntu:/boot# grep -i CONFIG_ACPI_HOTPLUG_MEMORY /boot/config-5.4.0-1040-kvm
CONFIG_ACPI_HOTPLUG_MEMORY=y

memory before memory hot-plugging:
root@ubuntu:/boot# free -k
              total used free shared buff/cache available
Mem: 4027608 149232 3621316 480 257060 3828108
Swap: 0 0 0

memory after memory hot-plugging:
root@ubuntu:/boot# free -k
              total used free shared buff/cache available
Mem: 10319064 249788 9802568 480 266708 9960284
Swap: 0 0 0