[Qemu-devel] [PATCH] vfio/pci-quirks: Only quirk to size of PCI config space

[Alex Williamson <alex.williamson@redhat.com>]

For quirks that support the full PCIe extended config space, limit the
quirk to only the size of config space available through vfio.  This
allows host systems with broken MMCONFIG regions to still make use of
these quirks without generating bad address faults trying to access
beyond the end of config space exposed through vfio.  This may expose
direct access to parts of extended config space that we'd prefer not
to expose, but that's why we have an IOMMU.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reported-by: Ronnie Swanink <ronnie@ronnieswanink.nl>
---
 hw/vfio/pci-quirks.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/hw/vfio/pci-quirks.c b/hw/vfio/pci-quirks.c
index 30c68a1..e117c41 100644
--- a/hw/vfio/pci-quirks.c
+++ b/hw/vfio/pci-quirks.c
@@ -328,7 +328,7 @@ static void vfio_probe_ati_bar4_quirk(VFIOPCIDevice *vdev, int nr)
     window->data_offset = 4;
     window->nr_matches = 1;
     window->matches[0].match = 0x4000;
-    window->matches[0].mask = PCIE_CONFIG_SPACE_SIZE - 1;
+    window->matches[0].mask = vdev->config_size - 1;
     window->bar = nr;
     window->addr_mem = &quirk->mem[0];
     window->data_mem = &quirk->mem[1];
@@ -674,7 +674,7 @@ static void vfio_probe_nvidia_bar5_quirk(VFIOPCIDevice *vdev, int nr)
     window->matches[0].match = 0x1800;
     window->matches[0].mask = PCI_CONFIG_SPACE_SIZE - 1;
     window->matches[1].match = 0x88000;
-    window->matches[1].mask = PCIE_CONFIG_SPACE_SIZE - 1;
+    window->matches[1].mask = vdev->config_size - 1;
     window->bar = nr;
     window->addr_mem = bar5->addr_mem = &quirk->mem[0];
     window->data_mem = bar5->data_mem = &quirk->mem[1];
@@ -765,7 +765,7 @@ static void vfio_probe_nvidia_bar0_quirk(VFIOPCIDevice *vdev, int nr)
     memory_region_init_io(mirror->mem, OBJECT(vdev),
                           &vfio_nvidia_mirror_quirk, mirror,
                           "vfio-nvidia-bar0-88000-mirror-quirk",
-                          PCIE_CONFIG_SPACE_SIZE);
+                          vdev->config_size);
     memory_region_add_subregion_overlap(&vdev->bars[nr].region.mem,
                                         mirror->offset, mirror->mem, 1);