[Intel-gfx] [PATCH] drm/i915/gvt: Disable access to stolen memory as a guest

[Chris Wilson]

Explicitly disable stolen memory when running as a guest in a virtual
machine, since the memory is not mediated between clients and reserved
entirely for the host. The actual size should be reported as zero, but
like every other quirk we want to tell the user what is happening.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Zhenyu Wang <zhenyuw at linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_gem_stolen.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index 154fbb04419f..0f0b37cad63d 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -417,6 +417,11 @@ int i915_gem_init_stolen(struct drm_device *dev)
 
 	mutex_init(&dev_priv->mm.stolen_lock);
 
+	if (intel_vgpu_active(dev_priv)) {
+		DRM_INFO("iGVT-g active, disabling use of stolen memory\n");
+		return 0;
+	}
+
 #ifdef CONFIG_INTEL_IOMMU
 	if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) {
 		DRM_INFO("DMAR active, disabling use of stolen memory\n");
-- 
2.10.2