FAILED: patch "[PATCH] drm/amdgpu/vcn3: add cancel_delayed_work_sync before power" failed to apply to 5.12-stable tree

The patch below does not apply to the 5.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to [off-list ref].

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 4a62542ae064e3b645d6bbf2295a6c05136956c6 Mon Sep 17 00:00:00 2001
From: James Zhu <redacted>
Date: Mon, 17 May 2021 16:39:17 -0400
Subject: [PATCH] drm/amdgpu/vcn3: add cancel_delayed_work_sync before power
 gate
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Add cancel_delayed_work_sync before set power gating state
to avoid race condition issue when power gating.

Signed-off-by: James Zhu <redacted>
Reviewed-by: Leo Liu <redacted>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c b/drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c
index 14470da52113..3b23de996db2 100644
--- a/drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c

@@ -372,15 +372,14 @@ static int vcn_v3_0_hw_init(void *handle)
 static int vcn_v3_0_hw_fini(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
-	struct amdgpu_ring *ring;
 	int i;
 
+	cancel_delayed_work_sync(&adev->vcn.idle_work);
+
 	for (i = 0; i < adev->vcn.num_vcn_inst; ++i) {
 		if (adev->vcn.harvest_config & (1 << i))
 			continue;
 
-		ring = &adev->vcn.inst[i].ring_dec;
-
 		if (!amdgpu_sriov_vf(adev)) {
 			if ((adev->pg_flags & AMD_PG_SUPPORT_VCN_DPG) ||
 					(adev->vcn.cur_state != AMD_PG_STATE_GATE &&