Commit e3ea2eae authored Apr 02, 2025 by Janusz Krzysztofik Committed by Jani Nikula Apr 09, 2025

drm/i915/huc: Fix fence not released on early probe errors

HuC delayed loading fence, introduced with commit 27536e03
("drm/i915/huc: track delayed HuC load with a fence"), is registered with
object tracker early on driver probe but unregistered only from driver
remove, which is not called on early probe errors.  Since its memory is
allocated under devres, then released anyway, it may happen to be
allocated again to the fence and reused on future driver probes, resulting
in kernel warnings that taint the kernel:

<4> [309.731371] ------------[ cut here ]------------
<3> [309.731373] ODEBUG: init destroyed (active state 0) object: ffff88813d7dd2e0 object type: i915_sw_fence hint: sw_fence_dummy_notify+0x0/0x20 [i915]
<4> [309.731575] WARNING: CPU: 2 PID: 3161 at lib/debugobjects.c:612 debug_print_object+0x93/0xf0
...
<4> [309.731693] CPU: 2 UID: 0 PID: 3161 Comm: i915_module_loa Tainted: G     U             6.14.0-CI_DRM_16362-gf0fd77956987+ #1
...
<4> [309.731700] RIP: 0010:debug_print_object+0x93/0xf0
...
<4> [309.731728] Call Trace:
<4> [309.731730]  <TASK>
...
<4> [309.731949]  __debug_object_init+0x17b/0x1c0
<4> [309.731957]  debug_object_init+0x34/0x50
<4> [309.732126]  __i915_sw_fence_init+0x34/0x60 [i915]
<4> [309.732256]  intel_huc_init_early+0x4b/0x1d0 [i915]
<4> [309.732468]  intel_uc_init_early+0x61/0x680 [i915]
<4> [309.732667]  intel_gt_common_init_early+0x105/0x130 [i915]
<4> [309.732804]  intel_root_gt_init_early+0x63/0x80 [i915]
<4> [309.732938]  i915_driver_probe+0x1fa/0xeb0 [i915]
<4> [309.733075]  i915_pci_probe+0xe6/0x220 [i915]
<4> [309.733198]  local_pci_probe+0x44/0xb0
<4> [309.733203]  pci_device_probe+0xf4/0x270
<4> [309.733209]  really_probe+0xee/0x3c0
<4> [309.733215]  __driver_probe_device+0x8c/0x180
<4> [309.733219]  driver_probe_device+0x24/0xd0
<4> [309.733223]  __driver_attach+0x10f/0x220
<4> [309.733230]  bus_for_each_dev+0x7d/0xe0
<4> [309.733236]  driver_attach+0x1e/0x30
<4> [309.733239]  bus_add_driver+0x151/0x290
<4> [309.733244]  driver_register+0x5e/0x130
<4> [309.733247]  __pci_register_driver+0x7d/0x90
<4> [309.733251]  i915_pci_register_driver+0x23/0x30 [i915]
<4> [309.733413]  i915_init+0x34/0x120 [i915]
<4> [309.733655]  do_one_initcall+0x62/0x3f0
<4> [309.733667]  do_init_module+0x97/0x2a0
<4> [309.733671]  load_module+0x25ff/0x2890
<4> [309.733688]  init_module_from_file+0x97/0xe0
<4> [309.733701]  idempotent_init_module+0x118/0x330
<4> [309.733711]  __x64_sys_finit_module+0x77/0x100
<4> [309.733715]  x64_sys_call+0x1f37/0x2650
<4> [309.733719]  do_syscall_64+0x91/0x180
<4> [309.733763]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
<4> [309.733792]  </TASK>
...
<4> [309.733806] ---[ end trace 0000000000000000 ]---

That scenario is most easily reproducible with
igt@i915_module_load@reload-with-fault-injection.

Fix the issue by moving the cleanup step to driver release path.

Fixes: 27536e03 ("drm/i915/huc: track delayed HuC load with a fence")
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/13592


Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Alan Previn <alan.previn.teres.alexis@intel.com>
Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Krzysztof Karas <krzysztof.karas@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://lore.kernel.org/r/20250402172057.209924-2-janusz.krzysztofik@linux.intel.com


(cherry picked from commit 795dbde9)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

parent a421f503

drivers/gpu/drm/i915/gt/uc/intel_huc.c

+5 −6

Original line number	Diff line number	Diff line
		@@ -317,6 +317,11 @@ void intel_huc_init_early(struct intel_huc *huc)
		}
		}

		void intel_huc_fini_late(struct intel_huc *huc)
		{
		delayed_huc_load_fini(huc);
		}

		#define HUC_LOAD_MODE_STRING(x) (x ? "GSC" : "legacy")
		static int check_huc_loading_mode(struct intel_huc *huc)
		{
		@@ -414,12 +419,6 @@ int intel_huc_init(struct intel_huc *huc)

		void intel_huc_fini(struct intel_huc *huc)
		{
		/*
		* the fence is initialized in init_early, so we need to clean it up
		* even if HuC loading is off.
		*/
		delayed_huc_load_fini(huc);

		if (huc->heci_pkt)
		i915_vma_unpin_and_release(&huc->heci_pkt, 0);

drivers/gpu/drm/i915/gt/uc/intel_huc.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -55,6 +55,7 @@ struct intel_huc {

		int intel_huc_sanitize(struct intel_huc *huc);
		void intel_huc_init_early(struct intel_huc *huc);
		void intel_huc_fini_late(struct intel_huc *huc);
		int intel_huc_init(struct intel_huc *huc);
		void intel_huc_fini(struct intel_huc *huc);
		int intel_huc_auth(struct intel_huc *huc, enum intel_huc_authentication_type type);

drivers/gpu/drm/i915/gt/uc/intel_uc.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -136,6 +136,7 @@ void intel_uc_init_late(struct intel_uc *uc)

		void intel_uc_driver_late_release(struct intel_uc *uc)
		{
		intel_huc_fini_late(&uc->huc);
		}

		/**