hw/pci: Use -1 as the default value for rombar

vfio_pci_size_rom() distinguishes whether rombar is explicitly set to 1
by checking dev->opts, bypassing the QOM property infrastructure.

Use -1 as the default value for rombar to tell if the user explicitly
set it to 1. The property is also converted from unsigned to signed.
-1 is signed so it is safe to give it a new meaning. The values in
[2 ^ 31, 2 ^ 32) become invalid, but nobody should have typed these
values by chance.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20250104-reuse-v18-13-c349eafd8673@daynix.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/include/hw/pci/pci_device.h b/include/hw/pci/pci_device.h
index 8eaf0d58bb..16ea7f4c19 100644
--- a/include/hw/pci/pci_device.h
+++ b/include/hw/pci/pci_device.h
@@ -148,7 +148,7 @@ struct PCIDevice {
     uint32_t romsize;
     bool has_rom;
     MemoryRegion rom;
-    uint32_t rom_bar;
+    int32_t rom_bar;
 
     /* INTx routing notifier */
     PCIINTxRoutingNotifier intx_routing_notifier;