diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index eafc376..158e74f 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -2494,7 +2494,6 @@
 void acpi_build(AcpiBuildTables *tables, MachineState *machine)
 {
     PCMachineState *pcms = PC_MACHINE(machine);
-    PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
     X86MachineState *x86ms = X86_MACHINE(machine);
     DeviceState *iommu = pcms->iommu;
     GArray *table_offsets;
@@ -2666,16 +2665,6 @@
             .rsdt_tbl_offset = &rsdt,
         };
         build_rsdp(tables->rsdp, tables->linker, &rsdp_data);
-        if (!pcmc->rsdp_in_ram) {
-            /* We used to allocate some extra space for RSDP revision 2 but
-             * only used the RSDP revision 0 space. The extra bytes were
-             * zeroed out and not used.
-             * Here we continue wasting those extra 16 bytes to make sure we
-             * don't break migration for machine types 2.2 and older due to
-             * RSDP blob size mismatch.
-             */
-            build_append_int_noprefix(tables->rsdp, 0, 16);
-        }
     }
 
     /* We'll expose it all to Guest so we want to reduce
@@ -2754,7 +2743,6 @@
 void acpi_setup(void)
 {
     PCMachineState *pcms = PC_MACHINE(qdev_get_machine());
-    PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
     X86MachineState *x86ms = X86_MACHINE(pcms);
     AcpiBuildTables tables;
     AcpiBuildState *build_state;
@@ -2816,25 +2804,10 @@
                            tables.vmgenid);
     }
 
-    if (!pcmc->rsdp_in_ram) {
-        /*
-         * Keep for compatibility with old machine types.
-         * Though RSDP is small, its contents isn't immutable, so
-         * we'll update it along with the rest of tables on guest access.
-         */
-        uint32_t rsdp_size = acpi_data_len(tables.rsdp);
-
-        build_state->rsdp = g_memdup(tables.rsdp->data, rsdp_size);
-        fw_cfg_add_file_callback(x86ms->fw_cfg, ACPI_BUILD_RSDP_FILE,
-                                 acpi_build_update, NULL, build_state,
-                                 build_state->rsdp, rsdp_size, true);
-        build_state->rsdp_mr = NULL;
-    } else {
-        build_state->rsdp = NULL;
-        build_state->rsdp_mr = acpi_add_rom_blob(acpi_build_update,
-                                                 build_state, tables.rsdp,
-                                                 ACPI_BUILD_RSDP_FILE);
-    }
+    build_state->rsdp = NULL;
+    build_state->rsdp_mr = acpi_add_rom_blob(acpi_build_update,
+                                             build_state, tables.rsdp,
+                                             ACPI_BUILD_RSDP_FILE);
 
     qemu_register_reset(acpi_build_reset, build_state);
     acpi_build_reset(build_state);