Totally unexpected that this regressed. Luckily it sounds like we just need to have dmar disable on the igfx, not the entire system. At least that's what a few days of testing between Tony Vroon and me indicates.

Reported-by: Tony Vroon tony@linx.net Cc: Tony Vroon tony@linx.net Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=43024 Signed-Off-by: Daniel Vetter daniel.vetter@ffwll.ch --- drivers/char/agp/intel-gtt.c | 1 - drivers/gpu/drm/i915/i915_dma.c | 17 ++++++++++++++++- drivers/gpu/drm/i915/i915_drv.c | 4 ++-- drivers/gpu/drm/i915/i915_drv.h | 2 +- include/drm/intel-gtt.h | 4 ++++ 5 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/drivers/char/agp/intel-gtt.c b/drivers/char/agp/intel-gtt.c index 7e223a2..e086fa5 100644 --- a/drivers/char/agp/intel-gtt.c +++ b/drivers/char/agp/intel-gtt.c @@ -1204,7 +1204,6 @@ static inline int needs_idle_maps(void) { #ifdef CONFIG_INTEL_IOMMU const unsigned short gpu_devid = intel_private.pcidev->device; - extern int intel_iommu_gfx_mapped;

/* Query intel_iommu to see if we need the workaround. Presumably that * was loaded first. diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c index 4636391..ee06241 100644 --- a/drivers/gpu/drm/i915/i915_dma.c +++ b/drivers/gpu/drm/i915/i915_dma.c @@ -1189,6 +1189,21 @@ static bool i915_switcheroo_can_switch(struct pci_dev *pdev) return can_switch; }

+static bool +intel_enable_ppgtt(struct drm_device *dev) +{ + if (i915_enable_ppgtt >= 0) + return i915_enable_ppgtt; + +#ifdef CONFIG_INTEL_IOMMU + /* Disable ppgtt on SNB if VT-d is on. */ + if (INTEL_INFO(dev)->gen == 6 && intel_iommu_gfx_mapped) + return false; +#endif + + return true; +} + static int i915_load_gem_init(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; @@ -1203,7 +1218,7 @@ static int i915_load_gem_init(struct drm_device *dev) drm_mm_init(&dev_priv->mm.stolen, 0, prealloc_size);

mutex_lock(&dev->struct_mutex); - if (i915_enable_ppgtt && HAS_ALIASING_PPGTT(dev)) { + if (intel_enable_ppgtt(dev) && HAS_ALIASING_PPGTT(dev)) { /* PPGTT pdes are stolen from global gtt ptes, so shrink the * aperture accordingly when using aliasing ppgtt. */ gtt_size -= I915_PPGTT_PD_ENTRIES*PAGE_SIZE; diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 0efc02e..c65907e 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -109,8 +109,8 @@ MODULE_PARM_DESC(enable_hangcheck, "WARNING: Disabling this can cause system wide hangs. " "(default: true)");

-bool i915_enable_ppgtt __read_mostly = 1; -module_param_named(i915_enable_ppgtt, i915_enable_ppgtt, bool, 0600); +int i915_enable_ppgtt __read_mostly = -1; +module_param_named(i915_enable_ppgtt, i915_enable_ppgtt, int, 0600); MODULE_PARM_DESC(i915_enable_ppgtt, "Enable PPGTT (default: true)");

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index b617cd5..1c8c440 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1088,7 +1088,7 @@ extern int i915_vbt_sdvo_panel_type __read_mostly; extern int i915_enable_rc6 __read_mostly; extern int i915_enable_fbc __read_mostly; extern bool i915_enable_hangcheck __read_mostly; -extern bool i915_enable_ppgtt __read_mostly; +extern int i915_enable_ppgtt __read_mostly;

extern int i915_suspend(struct drm_device *dev, pm_message_t state); extern int i915_resume(struct drm_device *dev); diff --git a/include/drm/intel-gtt.h b/include/drm/intel-gtt.h index 0a0001b..923afb5 100644 --- a/include/drm/intel-gtt.h +++ b/include/drm/intel-gtt.h @@ -44,4 +44,8 @@ void intel_gtt_insert_pages(unsigned int first_entry, unsigned int num_entries, /* flag for GFDT type */ #define AGP_USER_CACHED_MEMORY_GFDT (1 << 3)

+#ifdef CONFIG_INTEL_IOMMU +extern int intel_iommu_gfx_mapped; +#endif + #endif