Since it's implementation on v8.0.0-rc0, having the PCI_ERR_UNCOR_MASK
set for machine types < 8.0 will cause migration to fail if the target
QEMU version is < 8.0.0 :
qemu-system-x86_64: get_pci_config_device: Bad config data: i=0x10a read: 40
device: 0 cmask: ff wmask: 0 w1cmask:0
qemu-system-x86_64: Failed to load PCIDevice:config
qemu-system-x86_64: Failed to load e1000e:parent_obj
qemu-system-x86_64: error while loading state for instance 0x0 of device
'0000:00:02.0/e1000e'
qemu-system-x86_64: load of migration failed: Invalid argument
The above test migrated a 7.2 machine type from QEMU master to QEMU 7.2.0,
with this cmdline:
./qemu-system-x86_64 -M pc-q35-7.2 [-incoming XXX]
In order to fix this, property x-pcie-err-unc-mask was introduced to
control when PCI_ERR_UNCOR_MASK is enabled. This property is enabled by
default, but is disabled if machine type <= 7.2.
Fixes: 010746ae1d ("hw/pci/aer: Implement PCI_ERR_UNCOR_MASK register")
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Leonardo Bras <leobras@redhat.com>