On 03/26/2012 11:14 AM, Eduardo Habkost wrote:
On Mon, Mar 26, 2012 at 02:03:21PM +0200, Gleb Natapov wrote:
On Mon, Mar 26, 2012 at 01:59:05PM +0200, Avi Kivity wrote:
On 03/26/2012 01:24 PM, Jiri Denemark wrote:
...
The command line becomes unstable if you use -nodefconfig.
-no-user-config solves this but I fully expect libvirt would continue to use -nodefconfig.
Libvirt uses -nodefaults -nodefconfig because it wants to fully control how the virtual machine will look like (mainly in terms of devices). In other words, we don't want any devices to just magically appear without libvirt knowing about them. -nodefaults gets rid of default devices that are built directly in qemu. Since users can set any devices or command line options (such as enable-kvm) into qemu configuration files in @SYSCONFDIR@, we need to avoid reading those files as well. Hence we use -nodefconfig. However, we would still like qemu to read CPU definitions, machine types, etc. once they become externally loaded configuration (or however we decide to call it). That said, when CPU definitions are moved into @DATADIR@, and -no-user-config is introduced, I don't see any reason for libvirt to keep using -nodefconfig.
ACK.
I actually like -no-user-config more than -nodefconfig -readconfig @DATADIR@/... since it would avoid additional magic to detect what files libvirt should explicitly pass to -readconfig but basically any approach that would allow us to do read files only from @DATADIR@ is much better than what we have with -nodefconfig now.
That's how I see it as well.
+1
except that instead of -no-user-config we can do what most other programs do. If config file is specified during invocation default one is not used. After implementing -no-user-config (or similar) we can drop -nodefconfig entirely since its only user will be gone it its semantics is not clear.
Awesome. It looks like we have a solution now? Anthony, do you agree with that? Daniel, it looks good for you?
We cannot and should not drop -nodefconfig. But yes, I agree that we should introduce -no-user-config and use the semantics I specified earlier in the thread. Regards, Anthony Liguori