[PATCH 1/3] drm/i915/display: Do not assume zero offset when duplicating global state

[Gustavo Sousa <gustavo.sousa@intel.com>]

The current intel_*_duplicate_state() functions assume the offset for
the base member of their state structures is zero when calling
kmemdup(). While that is true today, such assumption should not be made
and proper offset must be applied when calling kmemdup(), otherwise we
will be duplicating the wrong memory area if, for some reason, the
offset is changed in the future.

As such, update each of those functions to use its respective
to_*_state() as the parameter to kmemdup().

Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
---
 drivers/gpu/drm/i915/display/intel_bw.c       | 4 ++--
 drivers/gpu/drm/i915/display/intel_cdclk.c    | 4 ++--
 drivers/gpu/drm/i915/display/intel_pmdemand.c | 4 ++--
 drivers/gpu/drm/i915/display/skl_watermark.c  | 4 ++--
 4 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c
index 08e8a67ca74c..30236010e0ed 100644
--- a/drivers/gpu/drm/i915/display/intel_bw.c
+++ b/drivers/gpu/drm/i915/display/intel_bw.c
@@ -1425,9 +1425,9 @@ int intel_bw_atomic_check(struct intel_atomic_state *state)
 static struct intel_global_state *
 intel_bw_duplicate_state(struct intel_global_obj *obj)
 {
-	struct intel_bw_state *state;
+	struct intel_bw_state *state = to_intel_bw_state(obj->state);
 
-	state = kmemdup(obj->state, sizeof(*state), GFP_KERNEL);
+	state = kmemdup(state, sizeof(*state), GFP_KERNEL);
 	if (!state)
 		return NULL;
 
diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c
index 3506e576bf6b..fc084e2a4c6a 100644
--- a/drivers/gpu/drm/i915/display/intel_cdclk.c
+++ b/drivers/gpu/drm/i915/display/intel_cdclk.c
@@ -3130,9 +3130,9 @@ static int fixed_modeset_calc_cdclk(struct intel_atomic_state *state)
 
 static struct intel_global_state *intel_cdclk_duplicate_state(struct intel_global_obj *obj)
 {
-	struct intel_cdclk_state *cdclk_state;
+	struct intel_cdclk_state *cdclk_state = to_intel_cdclk_state(obj->state);
 
-	cdclk_state = kmemdup(obj->state, sizeof(*cdclk_state), GFP_KERNEL);
+	cdclk_state = kmemdup(cdclk_state, sizeof(*cdclk_state), GFP_KERNEL);
 	if (!cdclk_state)
 		return NULL;
 
diff --git a/drivers/gpu/drm/i915/display/intel_pmdemand.c b/drivers/gpu/drm/i915/display/intel_pmdemand.c
index cdd314956a31..1f71efb7d04d 100644
--- a/drivers/gpu/drm/i915/display/intel_pmdemand.c
+++ b/drivers/gpu/drm/i915/display/intel_pmdemand.c
@@ -18,9 +18,9 @@
 static struct intel_global_state *
 intel_pmdemand_duplicate_state(struct intel_global_obj *obj)
 {
-	struct intel_pmdemand_state *pmdemand_state;
+	struct intel_pmdemand_state *pmdemand_state = to_intel_pmdemand_state(obj->state);
 
-	pmdemand_state = kmemdup(obj->state, sizeof(*pmdemand_state), GFP_KERNEL);
+	pmdemand_state = kmemdup(pmdemand_state, sizeof(*pmdemand_state), GFP_KERNEL);
 	if (!pmdemand_state)
 		return NULL;
 
diff --git a/drivers/gpu/drm/i915/display/skl_watermark.c b/drivers/gpu/drm/i915/display/skl_watermark.c
index 29e8ea91c858..b3d38e09df5a 100644
--- a/drivers/gpu/drm/i915/display/skl_watermark.c
+++ b/drivers/gpu/drm/i915/display/skl_watermark.c
@@ -3291,9 +3291,9 @@ static void skl_setup_wm_latency(struct drm_i915_private *i915)
 
 static struct intel_global_state *intel_dbuf_duplicate_state(struct intel_global_obj *obj)
 {
-	struct intel_dbuf_state *dbuf_state;
+	struct intel_dbuf_state *dbuf_state = to_intel_dbuf_state(obj->state);
 
-	dbuf_state = kmemdup(obj->state, sizeof(*dbuf_state), GFP_KERNEL);
+	dbuf_state = kmemdup(dbuf_state, sizeof(*dbuf_state), GFP_KERNEL);
 	if (!dbuf_state)
 		return NULL;
 
-- 
2.47.1