diff --git a/doc/dev/release-checklists.rst b/doc/dev/release-checklists.rst
index 834e66e89472b..29ca724da3147 100644
--- a/doc/dev/release-checklists.rst
+++ b/doc/dev/release-checklists.rst
@@ -98,6 +98,7 @@ Code cleanup
   `ceph_release_t::*`)
 - [ ] search code for `require_osd_release`
 - [ ] search code for `min_mon_release`
+- [ ] check include/denc.h if DENC_START macro still needs reference to squid
 
 QA suite
 --------
diff --git a/src/include/denc.h b/src/include/denc.h
index cdc54a55129e8..c06bf46bf24da 100644
--- a/src/include/denc.h
+++ b/src/include/denc.h
@@ -53,6 +53,7 @@
 #include "common/error_code.h"
 #include "common/likely.h"
 #include "ceph_release.h"
+#include "include/rados.h"
 
 template<typename T, typename=void>
 struct denc_traits {
@@ -1862,17 +1863,28 @@ inline std::enable_if_t<traits::supported && !traits::featured> decode_nohead(
   __u8 struct_compat = compat;						\
   char *_denc_pchar;							\
   uint32_t _denc_u32;							\
-  static_assert(CEPH_RELEASE >= (19/*squid*/ + 2) || compat == 1);	\
+  static_assert(CEPH_RELEASE >= (CEPH_RELEASE_SQUID /*19*/ + 2) || compat == 1);	\
   _denc_start(p, &struct_v, &struct_compat, &_denc_pchar, &_denc_u32);	\
   do {
 
-// For the only type that is with compat 2, osd_reqid_t, and unittest.
+// For the only type that is with compat 2: unittest.
 #define DENC_START_COMPAT_2(v, compat, p)				\
   __u8 struct_v = v;							\
   __u8 struct_compat = compat;						\
   char *_denc_pchar;							\
   uint32_t _denc_u32;							\
-  static_assert(CEPH_RELEASE >= (19/*squid*/ + 2) || compat == 2);	\
+  static_assert(CEPH_RELEASE >= (CEPH_RELEASE_SQUID /*19*/ + 2) || compat == 2);	\
+  _denc_start(p, &struct_v, &struct_compat, &_denc_pchar, &_denc_u32);	\
+  do {
+
+// For osd_reqid_t which cannot be upgraded at all.
+// We used it to communicate with clients and now we cannot safely upgrade.
+#define DENC_START_OSD_REQID(v, compat, p)				\
+  __u8 struct_v = v;							\
+  __u8 struct_compat = compat;						\
+  char *_denc_pchar;							\
+  uint32_t _denc_u32;							\
+  static_assert(compat == 2, "osd_reqid_t cannot be upgraded");		\
   _denc_start(p, &struct_v, &struct_compat, &_denc_pchar, &_denc_u32);	\
   do {
 
diff --git a/src/osd/osd_types.h b/src/osd/osd_types.h
index ee814f29678a4..fe62fad2805d3 100644
--- a/src/osd/osd_types.h
+++ b/src/osd/osd_types.h
@@ -164,7 +164,7 @@ struct osd_reqid_t {
   {}
 
   DENC(osd_reqid_t, v, p) {
-    DENC_START_COMPAT_2(2, 2, p);
+    DENC_START_OSD_REQID(2, 2, p);
     denc(v.name, p);
     denc(v.tid, p);
     denc(v.inc, p);