drm/amdkfd: CRIU return -EFAULT for copy_to_user() failure

If copy_to_user() fails, it returns the number of bytes remaining to
be copied but we want to return a negative error code (-EFAULT) to the
user.

Fixes: 9d5dabfe ("drm/amdkfd: CRIU Save Shared Virtual Memory ranges")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NDavid Yat Sin <david.yatsin@amd.com>
Reviewed-by: NFelix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: NFelix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdkfd/kfd_svm.c

@@ -3771,10 +3771,10 @@ int kfd_criu_checkpoint_svm(struct kfd_process *p,
 			goto exit_priv;
 		}
 
-		ret = copy_to_user(user_priv_data + *priv_data_offset,
-				   svm_priv, svm_priv_data_size);
-		if (ret) {
+		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
+				 svm_priv_data_size)) {
 			pr_err("Failed to copy svm priv to user\n");
+			ret = -EFAULT;
 			goto exit_priv;
 		}