1 files changed, 34 insertions, 12 deletions

diff --git a/migration/savevm.c b/migration/savevm.c
index e8a1b96fcd..48e85c052c 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -2117,6 +2117,13 @@ static int loadvm_postcopy_handle_resume(MigrationIncomingState *mis)
      */
     qemu_sem_post(&mis->postcopy_pause_sem_fault);
 
+    if (migrate_postcopy_preempt()) {
+        /* The channel should already be setup again; make sure of it */
+        assert(mis->postcopy_qemufile_dst);
+        /* Kick the fast ram load thread too */
+        qemu_sem_post(&mis->postcopy_pause_sem_fast_load);
+    }
+
     return 0;
 }
 
@@ -2540,16 +2547,6 @@ static bool postcopy_pause_incoming(MigrationIncomingState *mis)
 {
     int i;
 
-    /*
-     * If network is interrupted, any temp page we received will be useless
-     * because we didn't mark them as "received" in receivedmap.  After a
-     * proper recovery later (which will sync src dirty bitmap with receivedmap
-     * on dest) these cached small pages will be resent again.
-     */
-    for (i = 0; i < mis->postcopy_channels; i++) {
-        postcopy_temp_page_reset(&mis->postcopy_tmp_pages[i]);
-    }
-
     trace_postcopy_pause_incoming();
 
     assert(migrate_postcopy_ram());
@@ -2572,12 +2569,37 @@ static bool postcopy_pause_incoming(MigrationIncomingState *mis)
     mis->to_src_file = NULL;
     qemu_mutex_unlock(&mis->rp_mutex);
 
+    /*
+     * NOTE: this must happen before reset the PostcopyTmpPages below,
+     * otherwise it's racy to reset those fields when the fast load thread
+     * can be accessing it in parallel.
+     */
+    if (mis->postcopy_qemufile_dst) {
+        qemu_file_shutdown(mis->postcopy_qemufile_dst);
+        /* Take the mutex to make sure the fast ram load thread halted */
+        qemu_mutex_lock(&mis->postcopy_prio_thread_mutex);
+        migration_ioc_unregister_yank_from_file(mis->postcopy_qemufile_dst);
+        qemu_fclose(mis->postcopy_qemufile_dst);
+        mis->postcopy_qemufile_dst = NULL;
+        qemu_mutex_unlock(&mis->postcopy_prio_thread_mutex);
+    }
+
     migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE,
                       MIGRATION_STATUS_POSTCOPY_PAUSED);
 
     /* Notify the fault thread for the invalidated file handle */
     postcopy_fault_thread_notify(mis);
 
+    /*
+     * If network is interrupted, any temp page we received will be useless
+     * because we didn't mark them as "received" in receivedmap.  After a
+     * proper recovery later (which will sync src dirty bitmap with receivedmap
+     * on dest) these cached small pages will be resent again.
+     */
+    for (i = 0; i < mis->postcopy_channels; i++) {
+        postcopy_temp_page_reset(&mis->postcopy_tmp_pages[i]);
+    }
+
     error_report("Detected IO failure for postcopy. "
                  "Migration paused.");
 
@@ -2599,8 +2621,8 @@ retry:
     while (true) {
         section_type = qemu_get_byte(f);
 
-        if (qemu_file_get_error(f)) {
-            ret = qemu_file_get_error(f);
+        ret = qemu_file_get_error_obj_any(f, mis->postcopy_qemufile_dst, NULL);
+        if (ret) {
             break;
         }