diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c
index d125a4e..f731185 100644
--- a/arch/s390/kernel/ipl.c
+++ b/arch/s390/kernel/ipl.c
@@ -839,7 +839,7 @@
 	}
 	reipl_block_ccw->hdr.len = IPL_PARM_BLK_CCW_LEN;
 	reipl_block_ccw->hdr.version = IPL_PARM_BLOCK_VERSION;
-	reipl_block_ccw->hdr.blk0_len = sizeof(reipl_block_ccw->ipl_info.ccw);
+	reipl_block_ccw->hdr.blk0_len = IPL_PARM_BLK0_CCW_LEN;
 	reipl_block_ccw->hdr.pbt = DIAG308_IPL_TYPE_CCW;
 	/* check if read scp info worked and set loadparm */
 	if (SCCB_VALID)
@@ -880,8 +880,7 @@
 	} else {
 		reipl_block_fcp->hdr.len = IPL_PARM_BLK_FCP_LEN;
 		reipl_block_fcp->hdr.version = IPL_PARM_BLOCK_VERSION;
-		reipl_block_fcp->hdr.blk0_len =
-			sizeof(reipl_block_fcp->ipl_info.fcp);
+		reipl_block_fcp->hdr.blk0_len = IPL_PARM_BLK0_FCP_LEN;
 		reipl_block_fcp->hdr.pbt = DIAG308_IPL_TYPE_FCP;
 		reipl_block_fcp->ipl_info.fcp.opt = DIAG308_IPL_OPT_IPL;
 	}
@@ -930,7 +929,7 @@
 	}
 	dump_block_ccw->hdr.len = IPL_PARM_BLK_CCW_LEN;
 	dump_block_ccw->hdr.version = IPL_PARM_BLOCK_VERSION;
-	dump_block_ccw->hdr.blk0_len = sizeof(reipl_block_ccw->ipl_info.ccw);
+	dump_block_ccw->hdr.blk0_len = IPL_PARM_BLK0_CCW_LEN;
 	dump_block_ccw->hdr.pbt = DIAG308_IPL_TYPE_CCW;
 	dump_capabilities |= IPL_TYPE_CCW;
 	return 0;
@@ -954,7 +953,7 @@
 	}
 	dump_block_fcp->hdr.len = IPL_PARM_BLK_FCP_LEN;
 	dump_block_fcp->hdr.version = IPL_PARM_BLOCK_VERSION;
-	dump_block_fcp->hdr.blk0_len = sizeof(dump_block_fcp->ipl_info.fcp);
+	dump_block_fcp->hdr.blk0_len = IPL_PARM_BLK0_FCP_LEN;
 	dump_block_fcp->hdr.pbt = DIAG308_IPL_TYPE_FCP;
 	dump_block_fcp->ipl_info.fcp.opt = DIAG308_IPL_OPT_DUMP;
 	dump_capabilities |= IPL_TYPE_FCP;