[Qemu-devel] [PATCH 20/21] vfio-pci: Loosen sanity checks to allow future features

[Michael Roth <mdroth@linux.vnet.ibm.com>]

From: Alex Williamson <alex.williamson@redhat.com>

VFIO_PCI_NUM_REGIONS and VFIO_PCI_NUM_IRQS should never have been
used in this manner as it locks a specific kernel implementation.
Future features may introduce new regions or interrupt entries
(VGA may add legacy ranges, AER might add an IRQ for error
signalling).  Fix this before it gets us into trouble.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: qemu-stable@nongnu.org
(cherry picked from commit 8fc94e5a8046e349e07976f9bcaffbcd5833f3a2)

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 hw/vfio_pci.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hw/vfio_pci.c b/hw/vfio_pci.c
index 46dce55..283842d 100644
--- a/hw/vfio_pci.c
+++ b/hw/vfio_pci.c
@@ -1837,13 +1837,13 @@ static int vfio_get_device(VFIOGroup *group, const char *name, VFIODevice *vdev)
         error_report("Warning, device %s does not support reset\n", name);
     }
 
-    if (dev_info.num_regions != VFIO_PCI_NUM_REGIONS) {
+    if (dev_info.num_regions < VFIO_PCI_CONFIG_REGION_INDEX + 1) {
         error_report("vfio: unexpected number of io regions %u\n",
                      dev_info.num_regions);
         goto error;
     }
 
-    if (dev_info.num_irqs != VFIO_PCI_NUM_IRQS) {
+    if (dev_info.num_irqs < VFIO_PCI_MSIX_IRQ_INDEX + 1) {
         error_report("vfio: unexpected number of irqs %u\n", dev_info.num_irqs);
         goto error;
     }
-- 
1.7.9.5