[PATCH] drm/i915/huc: fix leak of debug object in huc load fence on driver unload

[Daniele Ceraolo Spurio]

The fence is always initialized in huc_init_early, but the cleanup in
huc_fini is only being run if HuC is enabled. This causes a leaking of
the debug object when HuC is disabled/not supported, which can in turn
trigger a warning if we try to register a new debug offset at the same
address on driver reload.

To fix the issue, make sure to always run the cleanup code.

Reported-by: Tvrtko Ursulin <tvrtko.ursulin at linux.intel.com>
Reported-by: Brian Norris <briannorris at chromium.org>
Fixes: 27536e03271d ("drm/i915/huc: track delayed HuC load with a fence")
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin at linux.intel.com>
Cc: Brian Norris <briannorris at chromium.org>
Cc: Alan Previn <alan.previn.teres.alexis at intel.com>
Cc: John Harrison <John.C.Harrison at Intel.com>
---

Note: I didn't manage to repro the reported warning, but I did confirm
that we weren't correctly calling i915_sw_fence_fini and that this patch
fixes that.

 drivers/gpu/drm/i915/gt/uc/intel_huc.c | 12 +++++++-----
 drivers/gpu/drm/i915/gt/uc/intel_uc.c  |  1 +
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_huc.c b/drivers/gpu/drm/i915/gt/uc/intel_huc.c
index fbc8bae14f76..83735a1528fe 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_huc.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_huc.c
@@ -300,13 +300,15 @@ int intel_huc_init(struct intel_huc *huc)
 
 void intel_huc_fini(struct intel_huc *huc)
 {
-	if (!intel_uc_fw_is_loadable(&huc->fw))
-		return;
-
+	/*
+	 * the fence is initialized in init_early, so we need to clean it up
+	 * even if HuC loading is off.
+	 */
 	delayed_huc_load_complete(huc);
-
 	i915_sw_fence_fini(&huc->delayed_load.fence);
-	intel_uc_fw_fini(&huc->fw);
+
+	if (intel_uc_fw_is_loadable(&huc->fw))
+		intel_uc_fw_fini(&huc->fw);
 }
 
 void intel_huc_suspend(struct intel_huc *huc)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc.c b/drivers/gpu/drm/i915/gt/uc/intel_uc.c
index dbd048b77e19..41f08b55790e 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_uc.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_uc.c
@@ -718,6 +718,7 @@ int intel_uc_runtime_resume(struct intel_uc *uc)
 
 static const struct intel_uc_ops uc_ops_off = {
 	.init_hw = __uc_check_hw,
+	.fini = __uc_fini, /* to clean-up the init_early initialization */
 };
 
 static const struct intel_uc_ops uc_ops_on = {
-- 
2.37.3