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From e7dfaf940021a366debea0eda5da28f572b76d9b Mon Sep 17 00:00:00 2001
From: ZhenGuo Yin <zhenguo.yin@amd.com>
Date: Wed, 12 Oct 2022 16:54:38 +0800
Subject: drm/amd/pm: Init pm_attr_list when dpm is disabled
Git-commit: 5fa993737b29bffe931cc5d0feb87ebc34cd5bb3
Patch-mainline: v6.1-rc2
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225 jsc#PED-2849
Alt-commit: 5af392a89bd009aced92e9079589bd82f249010a

[Why]
In SRIOV multi-vf, dpm is always disabled, and pm_attr_list won't
be initialized. There will be a NULL pointer call trace after
removing the dpm check condition in amdgpu_pm_sysfs_fini.
BUG: kernel NULL pointer dereference, address: 0000000000000000
RIP: 0010:amdgpu_device_attr_remove_groups+0x20/0x90 [amdgpu]
Call Trace:
  <TASK>
  amdgpu_pm_sysfs_fini+0x2f/0x40 [amdgpu]
  amdgpu_device_fini_hw+0xdf/0x290 [amdgpu]

[How]
List pm_attr_list should be initialized when dpm is disabled.

Fixes: a6ad27cec585fe ("drm/amd/pm: Remove redundant check condition")
Signed-off-by: ZhenGuo Yin <zhenguo.yin@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/amd/pm/amdgpu_pm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/pm/amdgpu_pm.c b/drivers/gpu/drm/amd/pm/amdgpu_pm.c
index 948cc75376f8..236657eece47 100644
--- a/drivers/gpu/drm/amd/pm/amdgpu_pm.c
+++ b/drivers/gpu/drm/amd/pm/amdgpu_pm.c
@@ -3362,11 +3362,11 @@ int amdgpu_pm_sysfs_init(struct amdgpu_device *adev)
 	if (adev->pm.sysfs_initialized)
 		return 0;
 
+	INIT_LIST_HEAD(&adev->pm.pm_attr_list);
+
 	if (adev->pm.dpm_enabled == 0)
 		return 0;
 
-	INIT_LIST_HEAD(&adev->pm.pm_attr_list);
-
 	adev->pm.int_hwmon_dev = hwmon_device_register_with_groups(adev->dev,
 								   DRIVER_NAME, adev,
 								   hwmon_groups);
-- 
2.38.1