[Intel-gfx] [PATCH v3 3/3] drm/i915/guc: Clear pointers on free

[John.C.Harrison at Intel.com]

From: John Harrison <John.C.Harrison at Intel.com>

Clear out some pointers when objects have been de-allocated. This
makes it much easier to track down use-after-free type issues.

Signed-off-by: John Harrison <John.C.Harrison at Intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
---
 drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c | 1 +
 drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c  | 1 +
 2 files changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c
index 7950d28beb8c..5212ff844292 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c
@@ -220,6 +220,7 @@ int intel_guc_ads_create(struct intel_guc *guc)
 void intel_guc_ads_destroy(struct intel_guc *guc)
 {
 	i915_vma_unpin_and_release(&guc->ads_vma, I915_VMA_RELEASE_MAP);
+	guc->ads_blob = NULL;
 }
 
 static void guc_ads_private_data_reset(struct intel_guc *guc)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
index 11742fca0e9e..fa9e048cc65f 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
@@ -210,6 +210,7 @@ void intel_guc_ct_fini(struct intel_guc_ct *ct)
 	GEM_BUG_ON(ct->enabled);
 
 	i915_vma_unpin_and_release(&ct->vma, I915_VMA_RELEASE_MAP);
+	memset(ct, 0, sizeof(*ct));
 }
 
 /**
-- 
2.25.1