From patchwork series 486380

https://patchwork.ozlabs.org//project/linuxppc-dev/list/?series=486380

Author: Fox Snowpatch

arch/powerpc/platforms/pseries/papr-hvpipe.c

@@ -209,7 +209,9 @@ static int hvpipe_rtas_recv_msg(char __user *buf, int size)
 			ret = copy_to_user(buf,
 					rtas_work_area_raw_buf(work_area),
 					bytes_written);
-			if (!ret)
+			if (ret)
+				ret = -EFAULT;
+			else
 				ret = bytes_written;
 		}
 	} else {
@@ -376,7 +378,7 @@ static ssize_t papr_hvpipe_handle_read(struct file *file,
 
 	ret = copy_to_user(buf, &hdr, HVPIPE_HDR_LEN);
 	if (ret)
-		return ret;
+		return -EFAULT;
 
 	/*
 	 * Message event has payload, so get the payload with