From: Chris Wilson <[email protected]> commit 6c76a93c453643e11a1063906c7c39168dd8d163 upstream.
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 <[email protected]> Cc: Mika Kuoppala <[email protected]> Cc: Martin Peres <[email protected]> Cc: Joonas Lahtinen <[email protected]> Cc: [email protected] Reviewed-by: Mika Kuoppala <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] (cherry picked from commit cec5ca08e36fd18d2939b98055346b3b06f56c6c) Signed-off-by: Rodrigo Vivi <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/gpu/drm/i915/gem/i915_gem_pm.c | 3 --- drivers/gpu/drm/i915/i915_drv.c | 5 +++++ drivers/gpu/drm/i915/selftests/i915_gem.c | 6 ++++++ 3 files changed, 11 insertions(+), 3 deletions(-) --- a/drivers/gpu/drm/i915/gem/i915_gem_pm.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_pm.c @@ -250,9 +250,6 @@ void i915_gem_resume(struct drm_i915_pri 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; --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -2238,6 +2238,11 @@ static int i915_drm_resume(struct drm_de 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); --- a/drivers/gpu/drm/i915/selftests/i915_gem.c +++ b/drivers/gpu/drm/i915/selftests/i915_gem.c @@ -117,6 +117,12 @@ static void pm_resume(struct drm_i915_pr with_intel_runtime_pm(&i915->runtime_pm, wakeref) { intel_gt_sanitize(i915, false); i915_gem_sanitize(i915); + + mutex_lock(&i915->drm.struct_mutex); + i915_gem_restore_gtt_mappings(i915); + i915_gem_restore_fences(i915); + mutex_unlock(&i915->drm.struct_mutex); + i915_gem_resume(i915); } }

