[v5 5/5] drm/amdgpu: fix invalid memory access in amdgpu_fence_driver_sw_fini()

[Jiang Liu <gerry@linux.alibaba.com>]

Introduce amdgpu_device_fini_schedulers() to clean scheduler related
resources, and avoid possible invalid memory access.

Signed-off-by: Jiang Liu <gerry@linux.alibaba.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 35 +++++++++++++++++++---
 drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c  |  9 ------
 2 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index ee695e70fb4f..dd94f87c1f7c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -2821,6 +2821,26 @@ static int amdgpu_device_fw_loading(struct amdgpu_device *adev)
 	return r;
 }
 
+static void __amdgpu_device_fini_schedulers(struct amdgpu_device *adev,
+					    int num_rings)
+{
+	int i;
+
+	for (i = 0; i < num_rings; ++i) {
+		struct amdgpu_ring *ring = adev->rings[i];
+
+		if (!ring || ring->no_scheduler)
+			continue;
+
+		drm_sched_fini(&ring->sched);
+	}
+}
+
+static void amdgpu_device_fini_schedulers(struct amdgpu_device *adev)
+{
+	__amdgpu_device_fini_schedulers(adev, AMDGPU_MAX_RINGS);
+}
+
 static int amdgpu_device_init_schedulers(struct amdgpu_device *adev)
 {
 	long timeout;
@@ -2857,27 +2877,32 @@ static int amdgpu_device_init_schedulers(struct amdgpu_device *adev)
 		if (r) {
 			DRM_ERROR("Failed to create scheduler on ring %s.\n",
 				  ring->name);
-			return r;
+			goto out_err;
 		}
 		r = amdgpu_uvd_entity_init(adev, ring);
 		if (r) {
 			DRM_ERROR("Failed to create UVD scheduling entity on ring %s.\n",
 				  ring->name);
-			return r;
+			goto out_sched_fini;
 		}
 		r = amdgpu_vce_entity_init(adev, ring);
 		if (r) {
 			DRM_ERROR("Failed to create VCE scheduling entity on ring %s.\n",
 				  ring->name);
-			return r;
+			goto out_sched_fini;
 		}
 	}
 
 	amdgpu_xcp_update_partition_sched_list(adev);
 
 	return 0;
-}
 
+out_sched_fini:
+	drm_sched_fini(&adev->rings[i]->sched);
+out_err:
+	__amdgpu_device_fini_schedulers(adev, i);
+	return r;
+}
 
 /**
  * amdgpu_device_ip_init - run init for hardware IPs
@@ -3424,6 +3449,8 @@ static int amdgpu_device_ip_fini(struct amdgpu_device *adev)
 
 	amdgpu_amdkfd_device_fini_sw(adev);
 
+	amdgpu_device_fini_schedulers(adev);
+
 	for (i = adev->num_ip_blocks - 1; i >= 0; i--) {
 		if (!adev->ip_blocks[i].status.sw)
 			continue;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
index 2f24a6aa13bf..c95895a7b888 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c
@@ -650,15 +650,6 @@ void amdgpu_fence_driver_sw_fini(struct amdgpu_device *adev)
 		if (!ring || !ring->fence_drv.initialized)
 			continue;
 
-		/*
-		 * Notice we check for sched.ops since there's some
-		 * override on the meaning of sched.ready by amdgpu.
-		 * The natural check would be sched.ready, which is
-		 * set as drm_sched_init() finishes...
-		 */
-		if (ring->sched.ops)
-			drm_sched_fini(&ring->sched);
-
 		for (j = 0; j <= ring->fence_drv.num_fences_mask; ++j)
 			dma_fence_put(ring->fence_drv.fences[j]);
 		kfree(ring->fence_drv.fences);
-- 
2.43.5