From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 0f4706d2740f2a221cd502922b22e522009041d9 upstream. We have reports of heavy screen corruption if we try to use the stolen memory reserved by the BIOS whilst the DMA-Remapper is active. This quirk may be only specific to a few machines or BIOSes, but first lets apply the big hammer and always disable use of stolen memory when DMAR is active. v2 by Jani: Rebase on -fixes, only look at intel_iommu_gfx_mapped. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=68535 Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx> Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> --- drivers/gpu/drm/i915/i915_gem_stolen.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c index fe4a7d16e261..c077df094ae5 100644 --- a/drivers/gpu/drm/i915/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c @@ -201,6 +201,13 @@ int i915_gem_init_stolen(struct drm_device *dev) struct drm_i915_private *dev_priv = dev->dev_private; int bios_reserved = 0; +#ifdef CONFIG_INTEL_IOMMU + if (intel_iommu_gfx_mapped) { + DRM_INFO("DMAR active, disabling use of stolen memory\n"); + return 0; + } +#endif + if (dev_priv->gtt.stolen_size == 0) return 0; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html