diff --git a/kmod/src/extents.h b/kmod/src/extents.h
index 2cba23ab..478892a8 100644
--- a/kmod/src/extents.h
+++ b/kmod/src/extents.h
@@ -18,6 +18,31 @@ struct scoutfs_extent {
 #define SE_ARG(ext)	(ext)->owner, (ext)->start, (ext)->len, (ext)->map, \
 			(ext)->type, (ext)->flags
 
+#define se_trace_define(name)			\
+	__field(__u64, name##_owner)		\
+	__field(__u64, name##_start)		\
+	__field(__u64, name##_len)		\
+	__field(__u64, name##_map)		\
+	__field(__u8, name##_type)		\
+	__field(__u8, name##_flags)
+
+/* doesn't support null extent pointers */
+#define se_trace_assign(name, ext)		\
+do {						\
+	__typeof__(ext) _ext = (ext);		\
+						\
+	__entry->name##_owner = _ext->owner;	\
+	__entry->name##_start = _ext->start;	\
+	__entry->name##_len = _ext->len;	\
+	__entry->name##_map = _ext->map;	\
+	__entry->name##_type = _ext->type;	\
+	__entry->name##_flags = _ext->flags;	\
+} while (0)
+
+#define se_trace_args(name) \
+	__entry->name##_owner, __entry->name##_start, __entry->name##_len, \
+	__entry->name##_map, __entry->name##_type, __entry->name##_flags
+
 enum {
 	SEI_NEXT,
 	SEI_PREV,
diff --git a/kmod/src/scoutfs_trace.h b/kmod/src/scoutfs_trace.h
index dc7568b0..e43084d0 100644
--- a/kmod/src/scoutfs_trace.h
+++ b/kmod/src/scoutfs_trace.h
@@ -446,7 +446,7 @@ TRACE_EVENT(scoutfs_data_alloc_block,
 	TP_STRUCT__entry(
 		__field(__u64, fsid)
 		__field(__u64, ino)
-		__field_struct(struct scoutfs_extent, ext)
+		se_trace_define(ext)
 		__field(__u64, iblock)
 		__field(__u64, len)
 		__field(__u64, online_blocks)
@@ -456,7 +456,7 @@ TRACE_EVENT(scoutfs_data_alloc_block,
 	TP_fast_assign(
 		__entry->fsid = FSID_ARG(sb);
 		__entry->ino = scoutfs_ino(inode);
-		__entry->ext = *ext;
+		se_trace_assign(ext, ext);
 		__entry->iblock = iblock;
 		__entry->len = len;
 		__entry->online_blocks = online_blocks;
@@ -464,7 +464,7 @@ TRACE_EVENT(scoutfs_data_alloc_block,
 	),
 
 	TP_printk("fsid "FSID_FMT" ino %llu ext "SE_FMT" iblock %llu len %llu online_blocks %llu offline_blocks %llu",
-		  __entry->fsid, __entry->ino, SE_ARG(&__entry->ext),
+		  __entry->fsid, __entry->ino, se_trace_args(ext),
 		  __entry->iblock, __entry->len, __entry->online_blocks,
 		  __entry->offline_blocks)
 );
@@ -476,18 +476,18 @@ TRACE_EVENT(scoutfs_data_alloc_block_ret,
 
 	TP_STRUCT__entry(
 		__field(__u64, fsid)
-		__field_struct(struct scoutfs_extent, ext)
+		se_trace_define(ext)
 		__field(int, ret)
 	),
 
 	TP_fast_assign(
 		__entry->fsid = FSID_ARG(sb);
-		__entry->ext = *ext;
+		se_trace_assign(ext, ext);
 		__entry->ret = ret;
 	),
 
 	TP_printk(FSID_FMT" ext "SE_FMT" ret %d", __entry->fsid,
-		SE_ARG(&__entry->ext), __entry->ret)
+		se_trace_args(ext), __entry->ret)
 );
 
 TRACE_EVENT(scoutfs_data_truncate_items,
@@ -2083,16 +2083,16 @@ DECLARE_EVENT_CLASS(scoutfs_extent_class,
 
 	TP_STRUCT__entry(
 		__field(__u64, fsid)
-		__field_struct(struct scoutfs_extent, ext)
+		se_trace_define(ext)
 	),
 
 	TP_fast_assign(
 		__entry->fsid = SCOUTFS_SB(sb) ? FSID_ARG(sb) : 0;
-		__entry->ext = *ext;
+		se_trace_assign(ext, ext);
 	),
 
 	TP_printk("fsid "FSID_FMT" ext "SE_FMT,
-		  __entry->fsid, SE_ARG(&__entry->ext))
+		  __entry->fsid, se_trace_args(ext))
 );
 
 DEFINE_EVENT(scoutfs_extent_class, scoutfs_extent_insert,