Re: [libvirt] [Qemu-devel] Modern CPU models cannot be used with libvirt

>> Yes, that's one reason. But maybe a user wants to have a whole >> different set of machine types and doesn't care to have the ones we >> provide. Why prevent a user from doing this? > > How are we preventing a user from doing it? In what way is -nodefconfig > helping it? Let me explain it in a different way, perhaps. We launch smbd in QEMU in order to do file sharing over slirp. One of the historic problems we've had is that we don't assume root privileges, yet want to be able to run smbd without using any of the system configuration files. You can do this by specify -s with the config file, and then in the config file you can overload the various default paths (like private dir, lock dir, etc.). In some cases, earlier versions of smbd didn't allow you to change private dir. You should be able to tell a well behaved tool not to read any configuration/data files and explicitly tell it where/how to read them. We cannot exhaustively anticipate every future use case of QEMU.

But beyond the justification for -nodefconfig, the fact is that it exists today, and has a specific semantic. If we want to have a different semantic, we should introduce a new option (-no-user-config).