From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mika Kuoppala Subject: Re: [PATCH 3/6] drm/i915: Perform GGTT restore much earlier during resume Date: Tue, 10 Sep 2019 13:39:38 +0300 Message-ID: <87y2ywsadx.fsf@gaia.fi.intel.com> References: <20190909110011.8958-1-chris@chris-wilson.co.uk> <20190909110011.8958-4-chris@chris-wilson.co.uk> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <20190909110011.8958-4-chris@chris-wilson.co.uk> Sender: stable-owner@vger.kernel.org To: intel-gfx@lists.freedesktop.org Cc: Chris Wilson , Martin Peres , Joonas Lahtinen , stable@vger.kernel.org List-Id: intel-gfx@lists.freedesktop.org Chris Wilson writes: > 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 > Cc: Mika Kuoppala > Cc: Martin Peres > Cc: Joonas Lahtinen > Cc: stable@vger.kernel.org Reviewed-by: Mika Kuoppala > --- > 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(-) > > 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); > diff --git a/drivers/gpu/drm/i915/selftests/i915_gem.c b/drivers/gpu/drm/i915/selftests/i915_gem.c > index bb6dd54a6ff3..37593831b539 100644 > --- a/drivers/gpu/drm/i915/selftests/i915_gem.c > +++ b/drivers/gpu/drm/i915/selftests/i915_gem.c > @@ -118,6 +118,12 @@ static void pm_resume(struct drm_i915_private *i915) > with_intel_runtime_pm(&i915->runtime_pm, wakeref) { > intel_gt_sanitize(&i915->gt, 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); > } > } > -- > 2.23.0