diff --git a/migration/migration.c b/migration/migration.c
index ecb4115d68..77b0c39b50 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -2308,7 +2308,7 @@ void qmp_migrate_set_cache_size(int64_t value, Error **errp)
     qmp_migrate_set_parameters(&p, errp);
 }
 
-int64_t qmp_query_migrate_cache_size(Error **errp)
+uint64_t qmp_query_migrate_cache_size(Error **errp)
 {
     return migrate_xbzrle_cache_size();
 }
@@ -2538,7 +2538,7 @@ int migrate_use_xbzrle(void)
     return s->enabled_capabilities[MIGRATION_CAPABILITY_XBZRLE];
 }
 
-int64_t migrate_xbzrle_cache_size(void)
+uint64_t migrate_xbzrle_cache_size(void)
 {
     MigrationState *s;
 
diff --git a/migration/migration.h b/migration/migration.h
index 0723955cd7..db6708326b 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -327,7 +327,7 @@ int migrate_multifd_zlib_level(void);
 int migrate_multifd_zstd_level(void);
 
 int migrate_use_xbzrle(void);
-int64_t migrate_xbzrle_cache_size(void);
+uint64_t migrate_xbzrle_cache_size(void);
 bool migrate_colo_enabled(void);
 
 bool migrate_use_block(void);
diff --git a/migration/page_cache.c b/migration/page_cache.c
index 098b436223..b384f265fb 100644
--- a/migration/page_cache.c
+++ b/migration/page_cache.c
@@ -38,7 +38,7 @@ struct PageCache {
     size_t num_items;
 };
 
-PageCache *cache_init(int64_t new_size, size_t page_size, Error **errp)
+PageCache *cache_init(uint64_t new_size, size_t page_size, Error **errp)
 {
     int64_t i;
     size_t num_pages = new_size / page_size;
diff --git a/migration/page_cache.h b/migration/page_cache.h
index 0cb94498a0..8733b4df6e 100644
--- a/migration/page_cache.h
+++ b/migration/page_cache.h
@@ -28,7 +28,7 @@ typedef struct PageCache PageCache;
  * @page_size: cache page size
  * @errp: set *errp if the check failed, with reason
  */
-PageCache *cache_init(int64_t cache_size, size_t page_size, Error **errp);
+PageCache *cache_init(uint64_t cache_size, size_t page_size, Error **errp);
 /**
  * cache_fini: free all cache resources
  * @cache pointer to the PageCache struct
diff --git a/migration/ram.c b/migration/ram.c
index 26adb55aa9..46e9d4d145 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -131,7 +131,7 @@ static void XBZRLE_cache_unlock(void)
  * @new_size: new cache size
  * @errp: set *errp if the check failed, with reason
  */
-int xbzrle_cache_resize(int64_t new_size, Error **errp)
+int xbzrle_cache_resize(uint64_t new_size, Error **errp)
 {
     PageCache *new_cache;
     int64_t ret = 0;
diff --git a/migration/ram.h b/migration/ram.h
index c25540cb93..6378bb3ebc 100644
--- a/migration/ram.h
+++ b/migration/ram.h
@@ -47,7 +47,7 @@ bool ramblock_is_ignored(RAMBlock *block);
     INTERNAL_RAMBLOCK_FOREACH(block)                   \
         if (!qemu_ram_is_migratable(block)) {} else
 
-int xbzrle_cache_resize(int64_t new_size, Error **errp);
+int xbzrle_cache_resize(uint64_t new_size, Error **errp);
 uint64_t ram_bytes_remaining(void);
 uint64_t ram_bytes_total(void);
 
diff --git a/qapi/migration.json b/qapi/migration.json
index 37026643ab..797f9edbc2 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -78,7 +78,7 @@
 # Since: 1.2
 ##
 { 'struct': 'XBZRLECacheStats',
-  'data': {'cache-size': 'int', 'bytes': 'int', 'pages': 'int',
+  'data': {'cache-size': 'size', 'bytes': 'int', 'pages': 'int',
            'cache-miss': 'int', 'cache-miss-rate': 'number',
            'encoding-rate': 'number', 'overflow': 'int' } }
 
@@ -1470,7 +1470,7 @@
 # <- { "return": 67108864 }
 #
 ##
-{ 'command': 'query-migrate-cache-size', 'returns': 'int',
+{ 'command': 'query-migrate-cache-size', 'returns': 'size',
   'features': [ 'deprecated' ] }
 
 ##