On Wed, Dec 19, 2012 at 08:38:13AM +0100, Gerd Hoffmann wrote:
On 12/19/12 08:24, Amos Kong wrote:
Current seabios will try to boot from selected devices first, if they are all failed, seabios will also try to boot from un-selected devices.
For example: @ qemu-kvm -boot order=n,menu=on ...
Guest will boot from network first, if it's failed, guest will try to boot from other un-selected devices (floppy, cdrom, disk) one by one.
Sometimes, user don't want to boot from some devices. This patch changes seabios to boot only from selected devices.
I think (i.e. I didn't test) the patch breaks booting if the user didn't explicitly specify a boot device.
Hi Gerd,
| #define DEFAULT_PRIO 9999
If we don't select some devices, their priority will always be 9999
| static int DefaultFloppyPrio = 101; | static int DefaultCDPrio = 102; | static int DefaultHDPrio = 103; | static int DefaultBEVPrio = 104;
The priority of selected devices will be changed to above values first, the priority might be re-changed.
However, we can judge if device is selected or not by checking if the priority is 9999.
. Boot guest without qemu boot option, guest will try to boot from network/hd/floppy/cdrom.
. If seabios ignores the order parameter of qemu, guest will also try to boot from network/hd/floppy/cdrom.