diff --git a/docs/specs/libxc-migration-stream.pandoc b/docs/specs/libxc-migration-stream.pandoc
index 8cd678f..18544e0 100644
--- a/docs/specs/libxc-migration-stream.pandoc
+++ b/docs/specs/libxc-migration-stream.pandoc
@@ -1,6 +1,8 @@
 % LibXenCtrl Domain Image Format
 % David Vrabel <<david.vrabel@citrix.com>>
   Andrew Cooper <<andrew.cooper3@citrix.com>>
+  Wen Congyang <<wency@cn.fujitsu.com>>
+  Yang Hongyang <<hongyang.yang@easystack.cn>>
 % Revision 1
 
 Introduction
@@ -227,7 +229,9 @@ type         0x00000000: END
 
              0x0000000E: CHECKPOINT
 
-             0x0000000F - 0x7FFFFFFF: Reserved for future _mandatory_
+             0x0000000F: CHECKPOINT_DIRTY_PFN_LIST (Secondary -> Primary)
+
+             0x00000010 - 0x7FFFFFFF: Reserved for future _mandatory_
              records.
 
              0x80000000 - 0xFFFFFFFF: Reserved for future _optional_
@@ -599,6 +603,26 @@ CHECKPOINT record or an END record.
 
 \clearpage
 
+CHECKPOINT_DIRTY_PFN_LIST
+------------
+
+A checkpoint dirty pfn list record is used to convey information about
+dirty memory in the VM. It is an unordered list of PFNs. Currently only
+applicable in the backchannel of a checkpointed stream.
+
+     0     1     2     3     4     5     6     7 octet
+    +-------------------------------------------------+
+    | pfn[0]                                          |
+    +-------------------------------------------------+
+    ...
+    +-------------------------------------------------+
+    | pfn[C-1]                                        |
+    +-------------------------------------------------+
+
+The count of pfns is: record->length/sizeof(uint64_t).
+
+\clearpage
+
 Layout
 ======
 
diff --git a/tools/libxc/xc_sr_common.c b/tools/libxc/xc_sr_common.c
index 945cfa6..3313a90 100644
--- a/tools/libxc/xc_sr_common.c
+++ b/tools/libxc/xc_sr_common.c
@@ -20,21 +20,22 @@ const char *dhdr_type_to_str(uint32_t type)
 
 static const char *mandatory_rec_types[] =
 {
-    [REC_TYPE_END]                  = "End",
-    [REC_TYPE_PAGE_DATA]            = "Page data",
-    [REC_TYPE_X86_PV_INFO]          = "x86 PV info",
-    [REC_TYPE_X86_PV_P2M_FRAMES]    = "x86 PV P2M frames",
-    [REC_TYPE_X86_PV_VCPU_BASIC]    = "x86 PV vcpu basic",
-    [REC_TYPE_X86_PV_VCPU_EXTENDED] = "x86 PV vcpu extended",
-    [REC_TYPE_X86_PV_VCPU_XSAVE]    = "x86 PV vcpu xsave",
-    [REC_TYPE_SHARED_INFO]          = "Shared info",
-    [REC_TYPE_TSC_INFO]             = "TSC info",
-    [REC_TYPE_HVM_CONTEXT]          = "HVM context",
-    [REC_TYPE_HVM_PARAMS]           = "HVM params",
-    [REC_TYPE_TOOLSTACK]            = "Toolstack",
-    [REC_TYPE_X86_PV_VCPU_MSRS]     = "x86 PV vcpu msrs",
-    [REC_TYPE_VERIFY]               = "Verify",
-    [REC_TYPE_CHECKPOINT]           = "Checkpoint",
+    [REC_TYPE_END]                          = "End",
+    [REC_TYPE_PAGE_DATA]                    = "Page data",
+    [REC_TYPE_X86_PV_INFO]                  = "x86 PV info",
+    [REC_TYPE_X86_PV_P2M_FRAMES]            = "x86 PV P2M frames",
+    [REC_TYPE_X86_PV_VCPU_BASIC]            = "x86 PV vcpu basic",
+    [REC_TYPE_X86_PV_VCPU_EXTENDED]         = "x86 PV vcpu extended",
+    [REC_TYPE_X86_PV_VCPU_XSAVE]            = "x86 PV vcpu xsave",
+    [REC_TYPE_SHARED_INFO]                  = "Shared info",
+    [REC_TYPE_TSC_INFO]                     = "TSC info",
+    [REC_TYPE_HVM_CONTEXT]                  = "HVM context",
+    [REC_TYPE_HVM_PARAMS]                   = "HVM params",
+    [REC_TYPE_TOOLSTACK]                    = "Toolstack",
+    [REC_TYPE_X86_PV_VCPU_MSRS]             = "x86 PV vcpu msrs",
+    [REC_TYPE_VERIFY]                       = "Verify",
+    [REC_TYPE_CHECKPOINT]                   = "Checkpoint",
+    [REC_TYPE_CHECKPOINT_DIRTY_PFN_LIST]    = "Checkpoint dirty pfn list",
 };
 
 const char *rec_type_to_str(uint32_t type)
diff --git a/tools/libxc/xc_sr_stream_format.h b/tools/libxc/xc_sr_stream_format.h
index 6d0f8fd..3291b25 100644
--- a/tools/libxc/xc_sr_stream_format.h
+++ b/tools/libxc/xc_sr_stream_format.h
@@ -60,21 +60,22 @@ struct xc_sr_rhdr
 /* Somewhat arbitrary - 8MB */
 #define REC_LENGTH_MAX                (8U << 20)
 
-#define REC_TYPE_END                  0x00000000U
-#define REC_TYPE_PAGE_DATA            0x00000001U
-#define REC_TYPE_X86_PV_INFO          0x00000002U
-#define REC_TYPE_X86_PV_P2M_FRAMES    0x00000003U
-#define REC_TYPE_X86_PV_VCPU_BASIC    0x00000004U
-#define REC_TYPE_X86_PV_VCPU_EXTENDED 0x00000005U
-#define REC_TYPE_X86_PV_VCPU_XSAVE    0x00000006U
-#define REC_TYPE_SHARED_INFO          0x00000007U
-#define REC_TYPE_TSC_INFO             0x00000008U
-#define REC_TYPE_HVM_CONTEXT          0x00000009U
-#define REC_TYPE_HVM_PARAMS           0x0000000aU
-#define REC_TYPE_TOOLSTACK            0x0000000bU
-#define REC_TYPE_X86_PV_VCPU_MSRS     0x0000000cU
-#define REC_TYPE_VERIFY               0x0000000dU
-#define REC_TYPE_CHECKPOINT           0x0000000eU
+#define REC_TYPE_END                        0x00000000U
+#define REC_TYPE_PAGE_DATA                  0x00000001U
+#define REC_TYPE_X86_PV_INFO                0x00000002U
+#define REC_TYPE_X86_PV_P2M_FRAMES          0x00000003U
+#define REC_TYPE_X86_PV_VCPU_BASIC          0x00000004U
+#define REC_TYPE_X86_PV_VCPU_EXTENDED       0x00000005U
+#define REC_TYPE_X86_PV_VCPU_XSAVE          0x00000006U
+#define REC_TYPE_SHARED_INFO                0x00000007U
+#define REC_TYPE_TSC_INFO                   0x00000008U
+#define REC_TYPE_HVM_CONTEXT                0x00000009U
+#define REC_TYPE_HVM_PARAMS                 0x0000000aU
+#define REC_TYPE_TOOLSTACK                  0x0000000bU
+#define REC_TYPE_X86_PV_VCPU_MSRS           0x0000000cU
+#define REC_TYPE_VERIFY                     0x0000000dU
+#define REC_TYPE_CHECKPOINT                 0x0000000eU
+#define REC_TYPE_CHECKPOINT_DIRTY_PFN_LIST  0x0000000fU
 
 #define REC_TYPE_OPTIONAL             0x80000000U
 
diff --git a/tools/python/xen/migration/libxc.py b/tools/python/xen/migration/libxc.py
index b0255ac..85a78f4 100644
--- a/tools/python/xen/migration/libxc.py
+++ b/tools/python/xen/migration/libxc.py
@@ -45,38 +45,40 @@ dhdr_type_to_str = {
 # Records
 RH_FORMAT = "II"
 
-REC_TYPE_end                  = 0x00000000
-REC_TYPE_page_data            = 0x00000001
-REC_TYPE_x86_pv_info          = 0x00000002
-REC_TYPE_x86_pv_p2m_frames    = 0x00000003
-REC_TYPE_x86_pv_vcpu_basic    = 0x00000004
-REC_TYPE_x86_pv_vcpu_extended = 0x00000005
-REC_TYPE_x86_pv_vcpu_xsave    = 0x00000006
-REC_TYPE_shared_info          = 0x00000007
-REC_TYPE_tsc_info             = 0x00000008
-REC_TYPE_hvm_context          = 0x00000009
-REC_TYPE_hvm_params           = 0x0000000a
-REC_TYPE_toolstack            = 0x0000000b
-REC_TYPE_x86_pv_vcpu_msrs     = 0x0000000c
-REC_TYPE_verify               = 0x0000000d
-REC_TYPE_checkpoint           = 0x0000000e
+REC_TYPE_end                        = 0x00000000
+REC_TYPE_page_data                  = 0x00000001
+REC_TYPE_x86_pv_info                = 0x00000002
+REC_TYPE_x86_pv_p2m_frames          = 0x00000003
+REC_TYPE_x86_pv_vcpu_basic          = 0x00000004
+REC_TYPE_x86_pv_vcpu_extended       = 0x00000005
+REC_TYPE_x86_pv_vcpu_xsave          = 0x00000006
+REC_TYPE_shared_info                = 0x00000007
+REC_TYPE_tsc_info                   = 0x00000008
+REC_TYPE_hvm_context                = 0x00000009
+REC_TYPE_hvm_params                 = 0x0000000a
+REC_TYPE_toolstack                  = 0x0000000b
+REC_TYPE_x86_pv_vcpu_msrs           = 0x0000000c
+REC_TYPE_verify                     = 0x0000000d
+REC_TYPE_checkpoint                 = 0x0000000e
+REC_TYPE_checkpoint_dirty_pfn_list  = 0x0000000f
 
 rec_type_to_str = {
-    REC_TYPE_end                  : "End",
-    REC_TYPE_page_data            : "Page data",
-    REC_TYPE_x86_pv_info          : "x86 PV info",
-    REC_TYPE_x86_pv_p2m_frames    : "x86 PV P2M frames",
-    REC_TYPE_x86_pv_vcpu_basic    : "x86 PV vcpu basic",
-    REC_TYPE_x86_pv_vcpu_extended : "x86 PV vcpu extended",
-    REC_TYPE_x86_pv_vcpu_xsave    : "x86 PV vcpu xsave",
-    REC_TYPE_shared_info          : "Shared info",
-    REC_TYPE_tsc_info             : "TSC info",
-    REC_TYPE_hvm_context          : "HVM context",
-    REC_TYPE_hvm_params           : "HVM params",
-    REC_TYPE_toolstack            : "Toolstack",
-    REC_TYPE_x86_pv_vcpu_msrs     : "x86 PV vcpu msrs",
-    REC_TYPE_verify               : "Verify",
-    REC_TYPE_checkpoint           : "Checkpoint",
+    REC_TYPE_end                        : "End",
+    REC_TYPE_page_data                  : "Page data",
+    REC_TYPE_x86_pv_info                : "x86 PV info",
+    REC_TYPE_x86_pv_p2m_frames          : "x86 PV P2M frames",
+    REC_TYPE_x86_pv_vcpu_basic          : "x86 PV vcpu basic",
+    REC_TYPE_x86_pv_vcpu_extended       : "x86 PV vcpu extended",
+    REC_TYPE_x86_pv_vcpu_xsave          : "x86 PV vcpu xsave",
+    REC_TYPE_shared_info                : "Shared info",
+    REC_TYPE_tsc_info                   : "TSC info",
+    REC_TYPE_hvm_context                : "HVM context",
+    REC_TYPE_hvm_params                 : "HVM params",
+    REC_TYPE_toolstack                  : "Toolstack",
+    REC_TYPE_x86_pv_vcpu_msrs           : "x86 PV vcpu msrs",
+    REC_TYPE_verify                     : "Verify",
+    REC_TYPE_checkpoint                 : "Checkpoint",
+    REC_TYPE_checkpoint_dirty_pfn_list  : "Checkpoint dirty pfn list"
 }
 
 # page_data
@@ -403,6 +405,10 @@ class VerifyLibxc(VerifyBase):
         if len(content) != 0:
             raise RecordError("Checkpoint record with non-zero length")
 
+    def verify_record_checkpoint_dirty_pfn_list(self, content):
+        """ checkpoint dirty pfn list """
+        raise RecordError("Found checkpoint dirty pfn list record in stream")
+
 
 record_verifiers = {
     REC_TYPE_end:
@@ -443,4 +449,6 @@ record_verifiers = {
         VerifyLibxc.verify_record_verify,
     REC_TYPE_checkpoint:
         VerifyLibxc.verify_record_checkpoint,
+    REC_TYPE_checkpoint_dirty_pfn_list:
+        VerifyLibxc.verify_record_checkpoint_dirty_pfn_list,
     }
