[PATCH] drm/amdgpu: amdgpu_device_recover_vram always failed if only one node in shadow_list

[wentalou]

amdgpu_bo_restore_shadow would assign zero to r if succeeded.
r would remain zero if there is only one node in shadow_list.
current code would always return failure when r <= 0.

Change-Id: Iae6880e7c78b71fde6a6754c69665c2e312a80a5
Signed-off-by: Wentao Lou <Wentao.Lou at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index c4c61e9..5cf21a4 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -3171,6 +3171,7 @@ static int amdgpu_device_recover_vram(struct amdgpu_device *adev)
 	struct dma_fence *fence = NULL, *next = NULL;
 	struct amdgpu_bo *shadow;
 	long r = 1, tmo;
+	bool single_shadow = false;
 
 	if (amdgpu_sriov_runtime(adev))
 		tmo = msecs_to_jiffies(8000);
@@ -3194,10 +3195,12 @@ static int amdgpu_device_recover_vram(struct amdgpu_device *adev)
 			r = dma_fence_wait_timeout(fence, false, tmo);
 			dma_fence_put(fence);
 			fence = next;
+			single_shadow = false;
 			if (r <= 0)
 				break;
 		} else {
 			fence = next;
+			single_shadow = true;
 		}
 	}
 	mutex_unlock(&adev->shadow_list_lock);
@@ -3206,7 +3209,8 @@ static int amdgpu_device_recover_vram(struct amdgpu_device *adev)
 		tmo = dma_fence_wait_timeout(fence, false, tmo);
 	dma_fence_put(fence);
 
-	if (r <= 0 || tmo <= 0) {
+	/* r would be zero even if amdgpu_bo_restore_shadow succeeded when single shadow in list */
+	if (r < 0 || (r == 0 && !single_shadow) || tmo <= 0) {
 		DRM_ERROR("recover vram bo from shadow failed\n");
 		return -EIO;
 	}
-- 
2.7.4