diff --git a/lustre/include/lustre/lustre_idl.h b/lustre/include/lustre/lustre_idl.h
index 8202adea5e3d5de1fab7d8bd3b170a6a77314e71..5db252b97413ff6e998d95c82681533788f64bf8 100644
--- a/lustre/include/lustre/lustre_idl.h
+++ b/lustre/include/lustre/lustre_idl.h
@@ -1237,13 +1237,14 @@ struct cfg_marker {
         __u32             cm_flags;
         __u32             cm_vers;       /* lustre release version number */
         __u32             padding;       /* 64 bit align */
-        time_t            cm_createtime; /*when this record was first created */
-        time_t            cm_canceltime; /*when this record is no longer valid*/
+        __u64             cm_createtime; /*when this record was first created */
+        __u64             cm_canceltime; /*when this record is no longer valid*/
         char              cm_tgtname[MTI_NAME_MAXLEN];
         char              cm_comment[MTI_NAME_MAXLEN];
 };
 
-extern void lustre_swab_cfg_marker(struct cfg_marker *marker);
+extern void lustre_swab_cfg_marker(struct cfg_marker *marker,
+                                   int swab, int size);
 
 /*
  * Opcodes for multiple servers.
diff --git a/lustre/obdclass/llog_swab.c b/lustre/obdclass/llog_swab.c
index 6522259ba96ffb2ff533b83417aa254e4450f08e..7bf539c0d925a5587c7a14eecec8b18c2a1c0f29 100644
--- a/lustre/obdclass/llog_swab.c
+++ b/lustre/obdclass/llog_swab.c
@@ -266,13 +266,64 @@ void lustre_swab_lustre_cfg(struct lustre_cfg *lcfg)
 }
 EXPORT_SYMBOL(lustre_swab_lustre_cfg);
 
-void lustre_swab_cfg_marker(struct cfg_marker *marker)
+/* used only for compatibility with old on-disk cfg_marker data */
+struct cfg_marker32 {
+        __u32   cm_step;
+        __u32   cm_flags;
+        __u32   cm_vers;
+        __u32   padding;
+        __u32   cm_createtime;
+        __u32   cm_canceltime;
+        char    cm_tgtname[MTI_NAME_MAXLEN];
+        char    cm_comment[MTI_NAME_MAXLEN];
+};
+
+#define MTI_NAMELEN32    (MTI_NAME_MAXLEN - \
+        (sizeof(struct cfg_marker) - sizeof(struct cfg_marker32)))
+
+void lustre_swab_cfg_marker(struct cfg_marker *marker, int swab, int size)
 {
+        struct cfg_marker32 *cm32 = (struct cfg_marker32*)marker;
         ENTRY;
 
-        __swab32s(&marker->cm_step);
-        __swab32s(&marker->cm_flags);
-        __swab32s(&marker->cm_vers);
+        if (swab) {
+                __swab32s(&marker->cm_step);
+                __swab32s(&marker->cm_flags);
+                __swab32s(&marker->cm_vers);
+        }
+        if (size == sizeof(*cm32)) {
+                __u32 createtime, canceltime;
+                /* There was a problem with the original declaration of
+                 * cfg_marker on 32-bit systems because it used time_t as
+                 * a wire protocol structure, and didn't verify this in
+                 * wirecheck.  We now have to convert the offsets of the
+                 * later fields in order to work on 32- and 64-bit systems.
+                 *
+                 * Fortunately, the cm_comment field has no functional use
+                 * so can be sacrificed when converting the timestamp size.
+                 *
+                 * Overwrite fields from the end first, so they are not
+                 * clobbered, and use memmove() instead of memcpy() because
+                 * the source and target buffers overlap.  bug 16771 */
+                createtime = cm32->cm_createtime;
+                canceltime = cm32->cm_canceltime;
+                memmove(marker->cm_comment, cm32->cm_comment, MTI_NAMELEN32);
+                marker->cm_comment[MTI_NAMELEN32 - 1] = '\0';
+                memmove(marker->cm_tgtname, cm32->cm_tgtname,
+                        sizeof(marker->cm_tgtname));
+                if (swab) {
+                        __swab32s(&createtime);
+                        __swab32s(&canceltime);
+                }
+                marker->cm_createtime = createtime;
+                marker->cm_canceltime = canceltime;
+                CDEBUG(D_CONFIG, "Find old cfg_marker(Srv32b,Clt64b) "
+                       "for target %s, converting\n",
+                       marker->cm_tgtname);
+        } else if (swab) {
+                __swab64s(&marker->cm_createtime);
+                __swab64s(&marker->cm_canceltime);
+        }
 
         EXIT;
         return;
diff --git a/lustre/obdclass/obd_config.c b/lustre/obdclass/obd_config.c
index 8799717666fc9012f6d3bd94e15e924db63784a2..754cea414756b447f6a599dfc4bb415bed36a6be 100644
--- a/lustre/obdclass/obd_config.c
+++ b/lustre/obdclass/obd_config.c
@@ -984,8 +984,8 @@ static int class_config_llog_handler(struct llog_handle * handle,
                 /* Figure out config state info */
                 if (lcfg->lcfg_command == LCFG_MARKER) {
                         struct cfg_marker *marker = lustre_cfg_buf(lcfg, 1);
-                        if (swab)
-                                lustre_swab_cfg_marker(marker);
+                        lustre_swab_cfg_marker(marker, swab,
+                                               LUSTRE_CFG_BUFLEN(lcfg, 1));
                         CDEBUG(D_CONFIG, "Marker, inst_flg=%#x mark_flg=%#x\n",
                                clli->cfg_flags, marker->cm_flags);
                         if (marker->cm_flags & CM_START) {
diff --git a/lustre/utils/wirecheck.c b/lustre/utils/wirecheck.c
index 85dd1ff1642a063c6774c9ff39e071594482b0a7..1e50887874a1e6575890148b39cc995c969dd18f 100644
--- a/lustre/utils/wirecheck.c
+++ b/lustre/utils/wirecheck.c
@@ -777,6 +777,19 @@ check_ldlm_lvb(void)
         CHECK_MEMBER(ost_lvb, lvb_blocks);
 }
 
+static void
+check_cfg_marker(void)
+{
+        BLANK_LINE();
+        CHECK_STRUCT(cfg_marker);
+        CHECK_MEMBER(cfg_marker, cm_step);
+        CHECK_MEMBER(cfg_marker, cm_flags);
+        CHECK_MEMBER(cfg_marker, cm_vers);
+        CHECK_MEMBER(cfg_marker, cm_createtime);
+        CHECK_MEMBER(cfg_marker, cm_canceltime);
+        CHECK_MEMBER(cfg_marker, cm_tgtname);
+        CHECK_MEMBER(cfg_marker, cm_comment);
+}
 
 static void
 check_llog_logid(void)
@@ -1383,6 +1396,7 @@ main(int argc, char **argv)
         check_ldlm_request();
         check_ldlm_reply();
         check_ldlm_lvb();
+        check_cfg_marker();
         check_llog_logid();
         check_llog_catid();
         check_llog_rec_hdr();