On gen 8 and later devices, the GTT stolen memory size when GGMS equals
0 is 0 (no preallocated memory) rather than 1MB [1].
[1] 3.1.13, 5th Generation Intel Core Processor Family Datasheet Vol. 2
https://www.intel.com/content/www/us/en/content-details/330835
Reported-By: Alex Williamson <alex.william...@redhat.com>
Signed-off-by: Tomita Moeko <tomitamo...@gmail.com>
---
hw/vfio/igd.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/hw/vfio/igd.c b/hw/vfio/igd.c
index 18d179bc83..09bd4e5383 100644
--- a/hw/vfio/igd.c
+++ b/hw/vfio/igd.c
@@ -259,7 +259,7 @@ static int vfio_igd_gtt_max(VFIOPCIDevice *vdev)
gmch = vfio_pci_read_config(&vdev->pdev, IGD_GMCH, sizeof(gmch));
ggms = (gmch >> (gen < 8 ? 8 : 6)) & 0x3;
- if (gen >= 8) {
+ if (gen >= 8 && ggms != 0) {
ggms = 1 << ggms;
}
@@ -669,7 +669,7 @@ void vfio_probe_igd_bar4_quirk(VFIOPCIDevice *vdev, int nr)
/* Determine the size of stolen memory needed for GTT */
ggms_mb = (gmch >> (gen < 8 ? 8 : 6)) & 0x3;
- if (gen >= 8) {
+ if (gen >= 8 && ggms_mb != 0) {
ggms_mb = 1 << ggms_mb;
}
--
2.45.2
