As soon as we re-enable the various functions within the HW, they may go
off and read data via a GGTT offset. Hence, if we have not yet restored
the GGTT PTE before then, they may read and even *write* random locations
in memory.
Detected by DMAR faults during resume.
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Mika Kuoppala <mika.kuoppala@xxxxxxxxxxxxxxx>
Cc: Martin Peres <martin.peres@xxxxxxxxxxxxxxx>
Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
drivers/gpu/drm/i915/gem/i915_gem_pm.c | 3 ---
drivers/gpu/drm/i915/i915_drv.c | 5 +++++
2 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pm.c b/drivers/gpu/drm/i915/gem/i915_gem_pm.c
index b3993d24b83d..9b1129aaacfe 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_pm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_pm.c
@@ -242,9 +242,6 @@ void i915_gem_resume(struct drm_i915_private *i915)
mutex_lock(&i915->drm.struct_mutex);
intel_uncore_forcewake_get(&i915->uncore, FORCEWAKE_ALL);
- i915_gem_restore_gtt_mappings(i915);
- i915_gem_restore_fences(i915);
-
if (i915_gem_init_hw(i915))
goto err_wedged;
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 7b2c81a8bbaa..1af4eba968c0 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1877,6 +1877,11 @@ static int i915_drm_resume(struct drm_device *dev)
if (ret)
DRM_ERROR("failed to re-enable GGTT\n");
+ mutex_lock(&dev_priv->drm.struct_mutex);
+ i915_gem_restore_gtt_mappings(dev_priv);
+ i915_gem_restore_fences(dev_priv);
+ mutex_unlock(&dev_priv->drm.struct_mutex);
+
intel_csr_ucode_resume(dev_priv);
i915_restore_state(dev_priv);
--
2.23.0
