Legacy IGD passthrough requires address 00:1f.0 to not be assigned to
anything on QEMU startup (currently it's assigned to bridge pci.2).
Changing this in general would break live-migration, so introduce a new
hostpci parameter "legacy-igd", which if set to 1 will move that bridge
to be nested under bridge 1.
This is safe because:
* Bridge 1 is unconditionally created on i440fx, so nesting is ok
* Defaults are not changed, i.e. PCI layout only changes when the new
parameter is specified manually
* hostpci forbids migration anyway
Additionally, the PT device has to be assigned address 00:02.0 in the
guest as well, which is usually used for VGA assignment. Luckily, IGD PT
requires vga=none, so that is not an issue either.
See https://git.qemu.org/?p=qemu.git;a=blob;f=docs/igd-assign.txt
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
projects / qemu-server.git / commit