-global lets you set a nice booby-trap for yourself:
$ qemu-system-x86_64 -nodefaults -S -display none -usb -monitor stdio -global usb-mouse.usb_version=l
QEMU 2.1.94 monitor - type 'help' for more information
(qemu) device_add usb-mouse
Parameter 'usb_version' expects an int64 value or range
$ echo $?
1
Not nice. Until commit 3196270 we even abort()ed.
The same error triggers if you manage to screw up a machine type's
compat_props. To demonstrate, change HW_COMPAT_2_1's entry to
.driver = "usb-mouse",\
.property = "usb_version",\
.value = "1", \
Then run
$ qemu-system-x86_64 -usb -M pc-i440fx-2.1 -device usb-mouse
upstream-qemu: -device usb-mouse: Parameter 'usb_version' expects an int64 value or range
$ echo $?
1
One of our creatively cruel error messages.
Since this is actually a coding error, we *should* abort() here.
Replace the error by an assertion failure in this case.
But turn the fatal error into a mere warning when the faulty
GlobalProperty comes from the user. Looks like this:
$ qemu-system-x86_64 -nodefaults -S -display none -usb -monitor stdio -global usb-mouse.usb_version=l
QEMU 2.1.94 monitor - type 'help' for more information
(qemu) device_add usb-mouse
Warning: global usb-mouse.usb_version=l ignored (Parameter 'usb_version' expects an int64 value or range)
(qemu)
This is consistent with how we handle similarly unusable -global in
qdev_prop_check_globals().
You could argue that the error should make device_add fail. Would be
harder, because we're running within TypeInfo's instance_post_init()
method device_post_init(), which can't fail.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>