On Thu, Jan 23, 2014 at 05:25:18PM +0100, Laszlo Ersek wrote:
On 01/23/14 15:58, Daniel P. Berrange wrote:
I disagree that users setting their persistent boot variables form inside the guest fall in the same category. That feature is an unalienable part of UEFI.
The goal we have is that the XML description should fully describe the configuration of a VM. Having a situation where the XML config only partially describes the setup, and the rest is delegated to a config embedded in the firmware image is not something we wish to support.
I understand.
IMHO what we need to tackle here is the inability to properly configure the firmware boot order from QEMU / libvirt. ie make it possible for users to fully control it via libvirt XML.
We'd face two hurdles towards this goal.
- The first is that you'd need to get a basically free-form string through. Technically it wouldn't be very hard, but it's completely foreign from the current bootindex concept in libvirt/qemu.
In UEFI, "bootable device" can refer to something that's just a chunk of guest RAM for qemu.
- The second hurdle is that you couldn't *offer* the host-side user sane choices (device paths for UEFI boot options) beyond a limit. This is because device paths come to existence by the execution and stacking of UEFI drivers, and their binding to devices.
Ok, I think I understand the problem more now. Would there be any sense in defining an generic <boot dev="config"/> option to indicate that UEFI should try the config settings that the user has defined inside the UEFI config partition ? If we use the strict=on|off setting, the user's config settings are only usable as the very last fallback option, once all the explicitly listed options have been tried. If we had a <boot dev="config"> we would perhaps be able to express ordering such as <boot dev="hd"> <boot dev="config"> <boot dev="cdrom"> without having to invent a impossibly complicated grammer to express all possible UEFI bootable device options ? Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|