When would you choose to use a Linux virtual machine instead of a docker container?
Is there something which a docker container can't be used for while a Linux virtual machine can?
Is it correct that if you require a Linux kernel version different from the host's, you can only use a virtual machine not a docker container? (I said so because I heard that a docker container use the same kernel as the host Linux.)
In particular, Docker and VirtualBox seem to put KVM/QEMU at disadvantage, because Docker can do what KVM/QEMU can and VirtualBox supports non-Linux guest better than KVM/QEMU.